05 Evaluate: Unit 02 Lesson 01 Graded Assignment

Choose the binary value for the decimal number 13.

1101

Choose the decimal value for the binary number 1010 .

10

Choose the next binary number in the following sequence.

10, 11, 100, 101....

110

Choose the value of 2¹ (two to the 1st power).

2

Choose the best description of what "digital sampling" does.

A) it converts decimal to binary

B) it creates digital approximations of analog values - ANSWER

C) it creates analog approximations of digital values

D) it converts binary to decimal

What is digital sampling? It creates a digital approximation of an analog value. The blue line below represents a sound going up and down in volume. Notice that the blue line has a smooth transition as it changes value. The red lines are examples of digital sampling that take place at regular intervals. Notice that the digital red sample lines approximate the waves created by the blue analog line.

Choose the best comparison between "digital" and "analog".

A) digital has smooth changes between values, analog does not

B) digital is for numbers and analog is for characters

C) digital and analog are the same thing

D) analog has smooth changes between values, digital does not - ANSWER

What does "analog" mean? It means something that is infinitely variable. It has a smooth, continuous transition from one value to another. Examples may make this more clear. Notice there is a picture of an analog speedometer at the top of the page. What makes it analog is that there is a needle that shows the value. The point to remember about a needle is that is can point to areas between numbers, and the transition as the needle moves is smooth.

What is "digital"? The opposite of analog is "digital". Digital information is typically numbers.  An example of a digital speedometer is one that just displays numbers like "61" or "59.5". The point to remember about digital is that it can only display numbers, not what is between them and its transition from one value to the next is not smooth, it is abrupt. For example, if you have a digital speedometer that can show tenths, it can display "59.5" or "59.6", but it cannot display any value that is between those two.

Choose the best description of what binary data can be used to represent.

A) numbers, characters, colors, and other types of data - ANSWER

B) binary data is not used by computers, only decimal data

C) only characters and numbers

D) only decimal numbers

How is information abstracted? Depending on the type of data being abstracted, binary numbers are used to represent non-numeric values. Here are some examples.

• numbers- a byte (8 bits that are either 1's or 0's) can represent 256 different numbers. If negative numbers are needed, then the leftmost bit can be set to 1 to indicate negative.  00000000 represents 0, 00000001 represents 1, and 10000001 represents -1.  In   Two bytes (16 bits) can represent numbers larger than 65 thousand. 

• letters and characters- These can also be represented as binary numbers, in the same way that letters of the alphabet can be represented by numbers. For example "a" can be represented by 1 because it is the 1st letter of the alphabet, and "z" can be represented by 26 because it is the last letter of the alphabet. Other characters, such as spaces and punctuation can be represented by different numbers. There is a standard for converting characters to binary numbers called ASCII (American Standard Code for Information Interchange).

• colors- Typically, colors can be described as a blend of three components: RGB (red, green, and blue). Each of these components is represented by a number that shows how much of it is in the color. The numbers are always in the order of red first, then green, then blue. The numbers 00000000 00000000 11111111 shows 0's for both the red and green and all 1's for the blue. Putting these three together would create a color that is all blue with no hints of red or green. The color 10100011 00000000 11001010 show fairly large numbers for both red and blue and all 0's for green. This would create a combined color that is purple.

• other data- Notice that 00000001 could represent the number 1, or a small amount of green, or some ASCII character. Different types of data can be represented by the same binary number. It depends on the context of what type of data the program expects to read.

Choose the best description of an "overflow" error.

A) when the program runs longer than expected

B) when a program puts data into a container that can't hold the data - ANSWER

C) when a program has a number so large it must be printed to the screen

D) when the program gets stuck in an infinite loop

What are "overflow" errors? Similar to rounding errors, overflow errors are due to the container. If you have a value that is above 200 billion, but the variable you are allowed to store it in can only contain numbers up to 2 billion, then there will certainly be an error when attempting to store the value.

Choose the best description of a byte.

A) 2 words 

B) 8 integers

C) 2 bits

D) 8 bits - ANSWER

byte- 8 bits grouped together is known as a "byte". A byte has 2⁸ (256) possible combinations of 1's and 0's, starting with 00000000, including 00000001, 00000010, and many others, all the way to 11111111.

Choose the smallest piece of data.

A) word

B) integer

C) bit - ANSWER

D) byte

bit- a single 1 or 0

byte- 8 bits

word- 2 or more bytes

integer- an unknown number of bytes, depending on the computer language