APCSP.Practice Test A

d

Internet users need to be able to transfer private data online, like credit card numbers and social security numbers. Some cryptographic algorithms help ensure this safety.

What makes cryptographic algorithms secure?

a. The algorithms used for cryptography are a secret.

b. The algorithms used for cryptography have been used for such a long time that we they are secure.

c. The algorithms used for cryptography are solvable, but the solutions are kept under a secure government protection service.

d. The algorithms used for cryptography are based on intractable (or unsolvable) problems, making them extremely difficult to break.

d

Alice posts a key for encrypting that anyone can access. Bob uses that key to encrypt a message, then sends it to Alice. When Alice receives the message, she decrypts it using a private key.

What kind of encryption process is this?

a. Vigenere cipher

b. Symmetric encryption

c. Certificate authority process

d. Public key encryption

b

What is a Distributed Denial of Service (DDoS) attack?

a. A coordinated effort by a group to simultaneously attempt to gain entry to foreign government's servers or systems

b. An attempt to compromise a single target by flooding it with requests from multiple systems.

c. An attempt to harass or extort all customers of one or more Internet Service Providers (ISPs).

d. An effort by network engineers to focus all systems on catching a user or computer that has illegally gained access.

a

When storing data digitally, whether through cloud computing or locally, there is an increased risk of theft due to the relative ease of accessing the information.

Which of the following is NOT an example of security and privacy concerns that arise from storing data digitally?

a. A manager looks up an employee's birthday in the online company directory in order to plan a surprise birthday party for them at the office.

b. An insurance company has a breach in their server that was accessed through stolen user credentials and more than 80 million records were compromised.

c. A company pays for a Distributed Denial of Service (DDoS) attack that shuts down a competitors website for an extended period of time.

d. A celebrity's phone is remotely accessed and photos are downloaded and sold to a magazine company.

b

Not all uses of data are for the greater good. One of the ways that hackers are able to abuse the system is to infiltrate systems and collect large data-sets that they are not supposed to have access to. This began with phone numbers and access to long distance calling and has transformed into a criminal environment where user identities are bought and sold on the black market.

Why might a hacker want to extract a user profile from an innocent site that has not financial connections?

a. Site data usually includes other sites visited in their search history.

b. Users might use similar passwords on other sites.

c. All sites are connected on the internet.

d. A user's name is all that is needed to breach a bank.

d

Which of the following scenarios is most characteristic of a phishing attack.

a. You get an unwanted email trying to sell you a low quality product or service that seems "fishy."

b. You accidentally install a piece of software that monitors your activity to steal personal information like your passwords, date of birth, social security number, etc.

c. You accidentally run a piece of code that automatically spreads from one computer to another, exploiting a common vulnerability

d. You get an email from the IT support desk that asks you to send a reply email with your username and password to verify your account

c

Caesar Cipher is an older and since outdated encryption technique used by Julius Caesar to "hide" messages he sent to his troops. Using Caesar Cipher, each letter in the alphabet is translated to a letter with the same given offset from the original letter. Characters that are not A-Z remain as is.

For example, if the message is HI ZOE and the shift is 2, the the encrypted message is: JK BQG since the letter "J" is two letters after "H" in the alphabet, and "K" is two letters after the "I" in the alphabet, etc. Notice that since the "Z" is at the end of the alphabet and the shift is 2, the algorithm has to wrap back around to the beginning of the alphabet so that "Z" translates to "B". Suppose that you want to encrypt the following message: REMAIN HOME. Of the following, which would be a potential encrypted message using Caesar Cipher?

a. TGPBKP JPQG

b. SFNCKO IPNF

c. UHPDLQ KRPH

d. PFLBHO INND

a

Fill in the blank of the following statement: "______ encryption is a method of encryption involving one key for both encryption and decryption."

a. Symmetric

b. SSL

c. Asymetric

d. Public Key

d

Ransomware is a relatively new form of attack on a computer system. A ransomware attack is when an individual or group of individuals targets an organization's server and is able to use a sophisticated form of enryption to lock down the organization's files. Effectively, the organization cannot gain access to their own data, causing major disruptions. The term "Ransomware" comes from the fact that the organization is asked for money in exchange for being granted access to their files.

Of the following, which is the LEAST effective way for an organization to protect against Ransomware?

a. Install anti-virus software on its servers.

b. Make sure that its operating system software updates are implemented on a frequent basis.

c. Educate its employees about cybersecurity concerns and how to proactively address them.

d. Make frequent backups of its data and store the backups online on the same server as the original data.

b

A coffee shop is considering accepting orders and payments through their phone app and have decided to use public key encryption to encrypt their customers' credit card information. Is this a secure form of payment?

a. No, public key encryption allows the credit card information to be read by the public.

b. Yes, public key encryption is built upon computationally hard problems that even powerful computers cannot easily solve.

c. No, the internet protocols are open standards and thus everything sent over the internet is sent "in the clear".

d. Yes, public key encryption is secure because it transmits credit card information in binary.

b

Choose the answer that is NOT a feature of Public Key Cryptography:

a. Using public key guarantees that only the intended recipient can decrypt the message

b. A Public Key database ensures 3rd party accountability of security

c. Allows secure communication without establishing a *shared* encryption key ahead of time.

d. A key for decrypting is never made public

a

Which of the following statements best describes the properties of public key encryption?

a. Public key encryption is an encryption method which relies on separate keys for encrypting and decrypting information.

b. Public key encryption makes use of certain types of problems which are easier for humans to solve than computers.

c. Public key encryption is a highly secure encryption scheme that in which a single shared key is used by both the sender and receiver of the message.

d. Public key encryption makes use of mathematical problems which no algorithm can be used to solve.

c

The term "protocol" is used quite a bit when referring to computer networks. Of the following, which is the BEST definition of "protocol"?

a. A protocol is the original model of a new device on the network.

b. A protocol is the "initial call" of a procedure to facilitate the transfer of data over the internet.

Selected: c. A protocol refers to the defined rules that allow two connection point to talk to each other.This answer is correct.

d. A protocol is the planning and design of a network, generally created by IT administrators.

IV & V

Choose 2: Which of the following statements are true about routing on the Internet?

I. Information travelling between two computers over the Internet will always take the same path.

II. Your router receives all the traffic currently travelling across the Internet and delivers to your computer only the messages intended for you.

III. There is one router which receives and redirects all the traffic of the Internet.

IV. A packet travelling between two computers on the Internet may be rerouted many times along the way.

V. A packet contains addressing information to allow routers to decide how best to forward along that packet towards its destination.

_ & _ (put the smaller number response first)

d

Which of the following statements about packets is TRUE?

a. Packets must be sent in order so they can be reassembled at the end host.

b. Packet switching results in a sustained connection between two hosts.

c. All packets must pass through a centralized router to be verified before reaching their destination.

Selected: d. None of these statements are true.

d

Which of the following is NOT a characteristic of the redundant nature of routing on the Internet?

a. The ability to reroute data when one connection is overloaded

b. The ability to transmit data between two devices even when some connections in the network are broken

c. The existence of multiple paths between two addresses

Selected: d. The ability to use a hierarchical naming system to avoid naming conflicts

d

Which of the following BEST describes how protocols on the Internet (e.g. IP, TCP, HTTP) make use of abstraction to accomplish their respective purposes?

a. High level protocols can take on the role of a low level protocol in the event of failure in the system.

b. Low level protocols are written in binary while high level protocols are written in hexadecimal.

c. High level protocols take into account specific implementation details of lower level protocols to ensure they are compatible.

Selected: d. Low level protocols can provide functionality to high level protocols without revealing the details of how this is accomplished.

III & IV

Which of the following statements are true about routers and routing on the Internet. Choose two answers.

I. Protocols ensure that a single path between two computers is established before sending packets over it.

II. Routers are hierarchical and the "root" router is responsible for communicating to sub-routers the best paths for them to route internet traffic.

III. A packet traveling between two computers on the internet may be rerouted many times along the way or even lost or "dropped".

IV. Routers act independently and route packets as they see fit.

_ & _ (put smallest number first, largest second)

d

A school starts tracking which websites each computer in the school is visiting by monitoring the packets leaving the school. A sample of the information they have collected appears below: Which of the following is MOST likely to be answerable using all the data collected by this monitoring?

a. Which students are visiting social media sites from school

b. Which classes are assigning the most homework using computers

c. Which programs students are running on the lab computers

Selected: d. Which websites are most frequently visited before and after school hours from a school computer

b

According to the Internet Protocol (IP), what information is contained in a packet?

a. The entirety of the data being transmitted, as well as control information for routing the data

Selected: b. A small chunk of the data being transmitted, as well as control information for routing the dataThis answer is correct.

c. The entirety of the data being transmitted

d. A small chunk of the data being transmitted

c

Which of the following is NOT true about TCP/IP packets?

a. Packets are numbered so if they arrive out of order the message can be reassembled

b. Packets can be routed on different paths from sender to receiver

Selected: c. TCP guarantees that no packets are ever droppedThis answer is correct.

d. Messages are broken into packets to improve reliability of the internet

d

A new device is given an IP address and added to a network so that it can access the Internet. Large amounts of files are uploaded and downloaded on this new device, but other users who were already online do not experience any difference in performance.

Which of the following enables this phenomenon?

a. Open standards and protocols

b. Fault tolerance

c. Hierarchical DNS

Selected: d. Redundant routers

b

How are protocols like HTTP, SMTP, and IP created?

a. Individuals make their own protocols for personal use.

Selected: b. A worldwide group of volunteers draft, revise, and publish protocols.This answer is correct.

c. Independent contractors are hired by companies to create protocols.

d. Individuals make their own protocols that occasionally catch on and are used by most of the Internet.

I & III

Choose the two true statements about HTTP:

I. An HTTP request is sent from a client to request access to data stored on a server.

II. HTTP requests and responses have identical formats.

III. Displaying a web page will often require multiple HTTP requests in order to acquire all the necessary data.

IV. An HTTP response code is only used when a server could not fulfill a request.

_ & _ (Put the smaller number response first)

II & IV

Choose two: Pick the two statements about packets and routing on the Internet which are true.

I. Packets travelling across the Internet take a standardized amount of time and so can be counted on to arrive in the order they were sent.

II. TCP ensures messages can be reliably transmitted across the Internet.

III. TCP depends on the infrastructure of the Internet to be reliable enough to ensure no packets are lost in transmission.

IV. TCP must account for the fact that packets may not arrive at a destination computer in the intended order.

_ & _ (put the smaller number response first)

II & III

Choose 2: If the post office delivered mail exactly like routers deliver messages on the Internet, which 2 of the following statements would be true?

I. One mail carrier would be responsible for delivering a letter from sender to receiver.

II. The mail carrier would sometimes take different paths to deliver each letter to your home.

III. Letters would be written on the outside of envelopes for all to read instead of being put inside envelopes.

IV. Your mail could not be delivered if a road your mail carrier was planning to take were under construction.

_ & _ (put the smaller number response first)

a

Which of the following is a benefit of the fault-tolerant nature of Internet routing?

Selected: a. The ability to provide data transmission even when some connections between routers have failedThis answer is correct.

b. The ability to use a hierarchical naming system to avoid naming conflicts

c. The ability to use multiple protocols such as hypertext transfer protocol (HTTP), Internet protocol (IP), and simple mail transfer protocol (SMTP) to transfer data.

d. The ability to resolve errors in domain name system (DNS) lookups

I and II

Question 18

A user enters a Web address in a browser, and a request for a file is sent to a Web server. Which of the following statements are true about how the file is sent to the user?

I - The file is broken down into several packets for transmission.

II - The packets must be reassembled by the user's device upon receipt.

III - The user's browser must request each individual packet, in order, until all packets are received

c

Which of the following is NOT true about packets?

a. Packets are numbered, so if they arrive out of order, the message can be reassembled.

b. The receiver computer must confirm to the sending computer that each packet was received.

Selected: c. A message sent across the Internet can always be contained in a single packet.This answer is correct.

d. Packets are routed on different paths from sender to receiver.

b

The figure below represents a network of physically linked computers labeled A through F. A line between two computers indicates that the computers can communicate directly with each other. Any information sent between two computers that are not directly connected must go through at least one other computer. For example, information can be sent directly between computers A and B, but information sent between computers A and C must go through other computers.

Which of the following statements are true about this network:

I - The network is fault tolerant. If a single connection fails, any two devices can still communicate.

II - Computers B and F need to first communicate with at least one other device in order to communicate with each other.

a. II only

Selected: b. I and IIThis answer is correct.

c. Neither I nor II

d. I only

d

The figure represents a network of physically linked computers labeled A through F. A line between two computers indicates that the computers can communicate directly with each other. Any information sent between two computers that are not directly connected must go through at least one other computer. The weight or cost of sending information from one computer to another is indicated by the number above the line.

For example, information can be sent directly between computers A, and B and will cost 5. Information sent between computers A and D must go through either computer C (with total cost 5), or through computer B(with total cost 8)

Question:

Computer A sends a packet intended to reach computerF. Along its path it arrives at Computer C. Which computer should Computer C forward the packet to in order to use the most cost effective path?

a. Computer F

b. Computer A

c. Computer B

Selected: d. Computer D

a

HTTP is considered to be a high-level protocol because:

Selected: a. HTTP requests make use of abstractions provided by lower-level protocols.This answer is correct.

b. HTTP requests are encoded using higher-frequency radio waves.

c. HTTP messages can be either requests or responses.

d. HTTP requests are given higher priority for fast delivery when being routed on the Internet.

I & II

Which of the following statements about redundancy on the Internet are TRUE? Select 2.

I. Redundancy has good qualities; if several routers fail, data can still be transferred.

II. Redundancy has good qualities; many devices can be added to the network without affecting traffic.

III. Redundancy has bad qualities; it creates unnecessary routers in the network.

IV. Redundancy has bad qualities; as more and more devices are added to the network, it takes longer for data to be transferred.

_ &_ (put smaller number response first)

II & III

The various protocols in use on the internet are said to operate in layers in which the protocol(s) at each layer solve one problem related to networked communication, and higher layers are built on top of, and rely on, the lower layers to do their jobs.

From the list provided choose the two (2) answers that correctly describe which internet protocol relies on the other. For example: if protocol A relies on protocol B, it means that A is a higher level protocol than B, and thus protocol B must exist and work properly in order for protocol A to do its job.

Select two answers

I. TCP/IP relies on HTTP

II. HTTP relies on TCP/IP

III. DNS relies on TCP/IP

IV. TCP/IP relies on DNS

_ & _ (put smaller number first, larger number second)

a

Let's assume that your Internet Service Provider (ISP) promotes that their bandwidth is 2 MB per second. The latency of a packet traveling from your favorite website's sever to your computer is 1 millisecond (ms).

Which of the following scenarios would MOST LIKELY have the greates potential for increasing the speed of information flow from your favorite website's server to your computer?

Selected: a. Your ISP changes its bandwidth to 2.5 MB per second, and latency from your favorite website's server to your computer is changed to 0.75 ms.This answer is correct.

b. Your ISP changes its bandwidth to 1.5 MB per second, and latency from your favorite website's server to your computer is changed to 1.5 ms.

c. Your ISP changes its bandwidth to 1.5 MB per second, and latency from your favorite website's server to your computer is changed to 0.75 ms.

d. Your ISP changes its bandwidth to 2.5 MB per second, and latency from you favorite website's server to your computer is changed to 1.5 ms.

b

Which of the following statements are true about Internet routing?

I - For any two Internet addresses, there exists only one path between the two addresses

II - Routing on the Internet is fault tolerant and redundant

a. I and II

Selected: b. II onlyThis answer is correct.

c. I only

d. Neither I nor II

d

Two different devices, built by different manufacturers, and running software built by different companies, are both connected to the Internet. Which of the following best describes the ability of the two computers to communicate with each other across the Internet?

a. The two devices cannot communicate since they are built by different manufacturers and are running different software

b. The two devices can communicate but only if the information being sent is encrypted

c. The two devices can communicate through an intermediary device that translates packets from one device into packets that are readable to the other device

Selected: d. The two devices can communicate directly because Internet communication uses standard protocols that all devices on the Internet abide by.

b

What is the Internet Protocol?

a. A law that says that the Internet is for everyone

Selected: b. A protocol that defines the structure of an Internet address and assigns a unique address to every device on the InternetThis answer is correct.

c. An agreement that sets a limit on the number of computers than can be on the Internet at any given time

d. A set of rules describing what behavior is acceptable on the Internet

False

TCP/IP is exactly two sets of protocols (TCP and IP)

True

Selected: False

ok

TCP/IP is actually called a "suite" of protocols because it contains many different protocols for using the Internet. The main protocols are TCP and IP.

c

Which of the following is a characteristic of the hierarchical nature of IP addresses?

a. The ability for one device to have multiple IP addresses at the same time

b. The ability to quickly translate domain names into IP addresses

Selected: c. The ability to quickly locate an IP address within a large networkThis answer is correct.

d. The ability to easily change the number of bits used to represent an IP address

d

Suppose we used an Internet Addressing protocol that used 8 bits to encode a single address. With this protocol, how many devices would be able to have their own unique address?

a. 128

b. 16

c. 64

Selected: d. 256

b

Which of the following statements about the Domain Name System (DNS) are true?

I - The Domain Name System is hierarchical

II - The Domain Name System was designed to be completely secure

a. Both I and II

Selected: b. I onlyThis answer is correct.

c. Neither I nor II

d. II only

True

TCP is a set of standards for how computers communicate with each other.

Selected: TrueThis answer is correct.

False

a

Which of the following best explains what happens when a new device is connected to the Internet?

Selected: a. An Internet Protocol (IP) address is assigned to the deviceThis answer is correct.

b. A router is assigned to the device

c. A server is assigned to the device

d. A domain name is assigned to the device

d

What is a Distributed Denial of Service (DDoS) attack?

a. An attempt by an Internet user to access private information stored in a private database

b. An attempt by one user to deny service to another user by posting malicious material on a social network

c. An attempt by a government to deny Internet access to its citizens

Selected: d. An attempt to deny access to a website by flooding the website's servers with millions of requests from different computers

b

How does a computer resolve a domain name into an IP address?

a. It uses a Border Gateway Protocol to get the address from a nearby computer

Selected: b. It asks a DNS server for the corresponding IP addressThis answer is correct.

c. It creates in IP address for the domain, and shares it with the closest DNS

d. It scans addresses until it finds the one it's looking for

d

Which of the following is a characteristic of the hierarchical nature of the domain name system (DNS)?

a. The ability to defend against DNS spoofing

b. The ability to provide data transmission even when some connections have failed

c. The ability to resend packets when they are unable to make it to their final destination

Selected: d. The ability to easily scale the system to allow for a large number of domain names

c

According to the domain name system (DNS), which of the following is a subdomain of the com top level domain?

a. example.com.gov

b. com.example.org

Selected: c. example.comThis answer is correct.

d. example.co.uk

c

Which of the following protocols is primarily used to establish a secure connection between browsers and servers so that no data is lost?

a. SMTP

b. HTTP

Selected: c. SSL/TLSThis answer is correct.

d. TCP/IP

d

A single central register of IP addresses and names (i.e. a DNS-style system) is an efficient means of translating human-readable names to IP addresses. Which of the following is NOT solved by DNS?

a. When an IP address changes, it is impossible to locate a computer until the owner announces the change.

b. It's inefficient to have everyone on the Internet maintain their own list of IP addresses.

c. When someone new joins the Internet, they need to inform everyone of their IP address.

Selected: d. There are too few IP addresses to meet the current demand.

c

Which of the following statements is an accurate interpretation of bandwidth speed?

a. The type of Internet service provided by a company.

b. The time it takes a piece of data to reach its destination.

Selected: c. The rate at which data is downloaded in a set amount of time.This answer is correct.

d. The number of files that can be downloaded in a set amount of time.

b

HTTP is an acronym for Hypertext Transfer Protocol. Of the following, which is the best definition of HTTP?

a. HTTP is a protocol used to create and implement web pages.

Selected: b. HTTP is the protocol for communicating with web servers and transferring web pages and other data back to a browser.This answer is correct.

c. HTTP is the address most people use to access a web page.

d. HTTP is the protocol for translating a web page's address to an Internet Protocol address.

a

According to the domain name system (DNS), which of the following is a subdomain of the domain test.com?

Selected: a. info.test.comThis answer is correct.

b. test.co.edu

c. test.gov

d. test.com.biz

b

Which of the following best describes the purpose of the domain name system (DNS)?

a. Encrypting information sent over the Internet

Selected: b. Translating domain names to IP addressesThis answer is correct.

c. Assigning a unique IP address to each new device connecting to the Internet

d. Sending packets of data between devices on the Internet

True

TCP/IP is the most widely used standard for packets and routing.

Selected: TrueThis answer is correct.

False

True

IP is a set of standards for routing and transferring information on a network.

Selected: TrueThis answer is correct.

False

d

According to the domain name system (DNS), which of the following is a subdomain of the domain example.com?

a. example.co.uk

b. example.org

c. example.com.org

Selected: d. about.example.com

a and c

Which of the following domain names are part of the same top tier?

Select TWO answers.

Selected: a. www.collegeA.eduThis answer is correct.

b. www.collegeB.com

Selected: c. www.collegeB.eduThis answer is correct.

d. www.collegeA.net

a

An IPv4 address has 32 bits, so there are 2^32 (over 4 billion) possible IPv4 addresses. Since the Internet is gaining devices quickly, we will soon surpass 4 2^32 unique devices on the Internet.

In anticipation of all the new Internet devices, we are in the process of switching to IPv6, which uses 128 bits for a single address. That's 96 extra bits to represent one address!

Which of the following statements correctly describes how many more addresses will be possible to represent by switching from IPv4 to IPv6?

Selected: a. 2^96 times as many addresses can be represented with IPv6This answer is correct.

b. 96 more addresses can be represented with IPv6

c. 2^96 more addresses can be represented with IPv6

d. 96 times as many addresses can be represented with IPv6

c

The world is currently in a transition to using IPv6, a newer version of the IP protocol that uses 128-bit addresses instead of 32-bit addresses used by IPv4. What is themain problem that IPv6 was created to solve?

a. IPv4 proved unreliable in some cases where network redundancy could not be ensured

b. IPv6 will allow problems with IPv4's address hierarchy to be resolved

Selected: c. 32-bit addresses could not ensure that every internet connected device can receive a unique IP addressThis answer is correct.

d. 32-bit addresses could not accommodate the increased size and amount of data traveling on the internet as it has grown in popularity

a

A bitmap picture can be represented by hexadecimal numbers. Each two-digit hexadecimal represents a row. To convert a number into a picture, one converts the hexadecimal into binary, then shades the bitmap according to the binary numbers. Each row represents one byte, that is, 8 bits.

A zero is a black square and a one is a white square.

Consider the following bitmap and the binary code. Which would be the correct code in hexadecimal?

11111111

11000011

11011011

11000011

11011011

11011011

11000011

11111111

a. FF C3 DB C3 DB DB C3 FFThis answer is correct.

b. FF 15 00 AA 84 F1 C3 C3

c. FF CC D1 22 DB F1 C3 FF

d. C3 11 00 56 8D FF 49 00

b

In order to send large files more quickly and in fewer packets, they are compressed. Which of the following statements is TRUE about a compressed text file?

a. You only need to send the compressed document because text compression has universal protocol.

Selected: b. You need to send the compressed text and the key.This answer is correct.

c. You need to send the compressed text, the key, and the original text. The original text is not accessed but is there in case the reassembly of the compressed text cannot be achieved, the computer can access the original file.

d. None of the above.

b

How many more values can be represented by one hexadecimal digit than one binary digit?

a. 4 times as many values

Selected: b. 8 times as many valuesThis answer is correct.

c. 2 times as many values

d. 16 times as many value

d

Which of the following statements are true about lossless compression?

I - Lossless compression is used only to send files over the Internet

II - Sending a compressed version of a file ensures that the contents of the file cannot be intercepted by an unauthorized user.

a. Both I and II

b. II only

c. I only

Selected: d. Neither I nor II

c

What is the minimum number of bits you would need to represent a number on a 0 to 10 scale?

a. 1

b. 10

Selected: c. 4This answer is correct.

d. 2

c

Digital images are often represented by the red, green, and blue values (an RGB triplet) of each individual pixel in the image. A photographer is manipulating a digital image and overwriting the original image. Which of the following describes a lossy transformation of the digital image (a transformation in which information is lost and cannot be restored)?

a. Creating a mirrored image by swapping the RGB values from pixels on the left side of an image with RGB values from pixels on the right side of an image.

b. Creating the negative of an image by creating a new RGB triplet for each pixel in which each value is calculated by subtracting the original value from 255. The negative of an image is reversed from the original; light areas appear dark, and colors are reversed.

Selected: c. Creating the gray scale of an image by averaging the amounts of red, green, and blue in each pixel and assigning this new value to the corresponding pixel in the new image. The new value of each pixel represents a shade of gray, ranging from white to black.This answer is correct.

d. Swapping the Red and Green values of each pixel so that areas that were red now appear green and vice versa.

c

What is the greatest value you can represent using 8 bits? (assuming all of them are positive numbers)

a. 256

b. 8

Selected: c. 255This answer is correct.

d. 7

d

Which of the following uses the symbols A through F?

a. binary

b. decimal

c. octal

Selected: d. hexadecimal

d

You are currently using a certain number of bits, n, to store values. Suppose you increase the number of bits you are using to store values by one. How many more values can you now represent?

a. Two more values

b. Ten times the number of values

c. One more value

Selected: d. Two times the number of values

ASCII is a character-encoding scheme that uses 7 bits to represent each character. The decimal (base 10) values 65 through 90 represent the capital letters A through Z, as shown in the table below.

What ASCII character is represented by the binary (base 2) number 1010001?

a. R

Selected: b. QThis answer is correct.

c. P

d. S

d

Which of the following is NOT a reason computers use hexadecimal?

a. Hexadecimal is a convenient way to represent colors.

b. Hexadecimal is a natural progression from binary.

c. Hexadecimal is convenient and brief.

Selected: d. Hexadecimal shows no relation to binary.

d

How many values can you represent with 3 binary digits?

a. 4

b. 16

c. 3

Selected: d. 8

a

Binary representation can be used to denote different types of information. Given that you only have 3 bits to store some data, which of the following can be best represented in these three bits?

Selected: a. The number of dots shown on the top face of a standard die after rolling it in a board game.This answer is correct.

b. The number of face cards (jacks, queens, kings) not yet dealt from a standard deck of 52 cards.

c. The number of pins knocked over in the first frame of a bowling game.

d. The number of holes played in the first three hours of a round of golf.

b

A byte is made up of 8 bits (binary digits). You have a programming language that uses one byte to represent characters and are now modifying your language to use two bytes to represent characters. How many more characters can you represent in your new programming language?

a. 8^2 times as many character

Selected: b. 2^8 times as many charactersThis answer is correct.

c.

2 times as many characters

d. 8 times as many characters

c

Using an ASCII table, the word vim can be represented in a number of ways. They include:

Hexadecimal: 76 69 6D

Decimal: 118 105 109

Binary: 01110110 01101001 01101101

Why do computer scientists often prefer hexadecimal over other representations?

a. Early typesetting procedures that predate modern computing used a base 16 system to represent alpha-numeric characters.

b. Computers, at their most basic, use hexadecimal, not decimal or binary.

Selected: c. Hexadecimal uses fewer digits than binary.This answer is correct.

d. Hexadecimal representations use letters as well as numbers.

c

Consider the following:

1011 0111 0110 0010

This sequence represents:

a. a number

b. instructions for the computer

Selected: c. something that depends on the context in which it is usedThis answer is correct.

d. data

c

Which of the following scenarios cannot be represented by a boolean variable?

a. Whether an exam is complete or incomplete

b. Whether a light switch is on or off

Selected: c. The value of an ASCII characterThis answer is correct.

d. Whether a letter is a capital letter or not

c

A video viewing Website previously used 32-bit integers to store the number of views for each video, but a video that had been watched billions of times hit the maximum value. What is it called when this maximum is exceeded?

a. A viewing error

b. A kilobyte error

Selected: c. An overflow errorThis answer is correct.

d. A maximum error

d

How many possible values can you represent with 2 binary digits?

a. 2

b. 8

c. 0

Selected: d. 4

a

IPv4 represents internet addresses with 32 bits, and the newer protocol IPv6 represents them with 128 bits. Which describes best how many addresses can be represented with IPv6 compared to IPv4?

Selected: a. 2^96 times as many addresses can be usedThis answer is correct.

b. 96^2 times as many addresses can be used

c. 96 times as many addresses can be used

d. 2^128 times as many addresses can be use

a

Which of the following statements are true about lossy compression?

I - Lossy compression can compress data down to significantly less bits than lossless compression can

II - Data compressed using a lossy compression technique cannot be restored back to its original state

Selected: a. Both I and IIThis answer is correct.

b. Neither I nor II

c. I only

d. II only

c

A researcher is emailing images of soil samples back to her lab so her team can analyze them. She notices that the images sent in her email are of lower quality than the images on her camera. Which of the following could be a possible explanation for the difference in image quality?

a. Some information was lost due to network packets not reaching their final destination

b. Before being sent, the image was compressed using a lossless compression technique

Selected: c. Before being sent, the image was compressed using a lossy compression techniqueThis answer is correct.

d. Before being sent, the image was encrypted using asymmetric encryption

b

What are the implications of Moore's Law?

a. Companies that are developing new technology need to be preparing for a drop-off in computing power.

Selected: b. Industry has expected an increase in computing power, resulting in more research and development of circuits, computer processors, sensors, and other technologies.This answer is correct.

c. Debugging should be done frequently, since mistakes are easier to locate in smaller segments of code.

d. None of the above.

a

In 2008, Google decided to compare search term trends with the CDS's recorded flu trends. They went to work trying to determine a pattern with previous years' data and use this data to predict future flu outbreaks.

Which of the following is MOST accurate about using search trends, like Google Flu Trends, as predictors of future events?

Selected: a. They are unreliable predictors of future events that might not accurately represent society as a whole.This answer is correct.

b. They are reliable predictors of future events that might not accurately represent society as a whole.

c. They are reliable predictors of future events that accurately represent society as a whole.

d. They are unreliable predictors of future events that accurately represent society as a whole.

b and c

What are the negative effects of global postioning systems (GPS) and other related technologies?

Select TWO answers.

a. Directions given by many GPS devices are not descriptive enough.

Selected: b. Drivers become reliant on GPS directions and struggle to navigate without them.This answer is correct.

Selected: c. The on screen directions from a GPS are distracting and can cause drivers to get in accidents.This answer is correct.

d. GPS systems are often out of date and therefore do not have current maps and directions.

a

Which of the following is NOT a potential outcome of governmental censorship of the Internet?

Selected: a. Governments could have complete control over what users see online.This answer is correct.

b. Each country might have a different version of the same basic social media platform.

c. Information could only flow withing countries, never leaving the country where it originated.

d. Each country could have its own version of the Internet with different content being filtered out.

ok

Even with all this censorship, the government never has complete control - there are many tools that users can access to bypass any censored websites.

b and d

Which of the following are examples of how video conferencing has changed the business world?

Select TWO answers.

a. Video conference calls are less engaging than traditional conference calls.

Selected: b. Employees can work remotely from home, saving the company money on facilities.This answer is correct.

c. Businesses have gone under because of their lack of technology like video conferencing software.

Selected: d. Companies have fewer safety issues and travel costs, as the employees do not have to travel across the country or world.

a

How could machine learning potentially change the field of medicine?

a. A computer that learns from its mistakes could be more reliable, consistent, and successful than a human doctor.This answer is correct.

b. Health-related apps could help patients be more informed of their own health and help them make better choices.

c. A database of all diseases and treatments known to mankind could help doctors make better choices when it comes to individual patients.

d. An online system for scheduling doctor's appointments could help more patients get help in a timely manner.

b

Which of the following describes a limitation of cloud computing?

a. Cloud computing has a negative effect on the scalability of systems

Selected: b. Storing data using cloud computing rather than storing on a personal computer may weaken the security of dataThis answer is correct.

c. Cloud computing is useful for individuals but not useful for businesses or governments

d. Cloud computing has a negative effect on communication and collaboration among teams of people

d

Which of the following could NOT be predicted using search trends?

a. The winner of an upcoming election.

b. The fluctuations of a company's stock.

c. The most popular travel destinations for any season.

Selected: d. All of these could be predicted using search trends.

c

A city government is attempting to reduce the digital divide between groups with differing access to computing and the Internet.

Which of the following actions is MOST likely to be effective in this purpose?

a. Putting all government forms on the city Website

b. Providing a way for citizens to vote online in local elections

Selected: c. Providing free wireless Internet connections at locations in low-income neighborhoodsThis answer is correct.

d. Providing online basic computing classes for free

b

Which of the following is a benefit that online shopping websites provide over brick and mortar stores?

a. There is no wait time between purchasing an item and having access to it

Selected: b. Users can easily see product reviews and determine if an item has been satisfactory for a large number of peopleThis answer is correct.

c. Users can easily pay with cash in person

d. Users can try out an item before they buy it

a

Which of the following statements are true about the Internet?

I - The Internet connects devices and networks all over the world

II - The Internet helps people collaborate to solve problems

III - The Internet helps people communicate

IV - There are no negative consequences of the Internet, it is purely positive

Selected: a. I, II, and IIIThis answer is correct.

b. I and II only

c. I, II, III, and IV

d. I only

I & III

Choose the two best answers to complete the sentence:

If I understand how the internet works then I will be able to :

I. make informed choices to support or oppose decisions my government makes about access to the internet

II. connect the latest devices to the internet

III. make informed choices about my privacy on the internet

IV. get the best price for my cell phone plan

V. speed up my downloads of movies I purchase

_ & _ ( put in order smallest first, lagest second)

d

What is the purpose of the Digital Millennium Copyright Act?

a. To make all content on the Internet free for everyone to use.

b. To criminalize plagiarism on the Internet.

c. To allow for open source software on the Internet.

Selected: d. To criminalize the act of circumventing, or getting around, access controls that block access to copyrighted works.

10

9 bits is enough to represent 512 different numbers. How many total bits do you need to represent 1024 (twice as many) numbers?

6

How many bits does it take to make the binary equivalent for 39?

True

The AP score for the Computer Science Principles is based on 2 performance tasks completed in class and a multiple choice test at the end of the course.

True or False?