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Elimination principle
The principle that in a competitive market, above normal profits are eliminated by entry and below normal profits are eliminated by exit.
Above normal profits are temporary
Invisible Hand Property 1
By producing where P = MC, profit seeking behavior results in the minimization of the total industry costs of production.
Invisible Hand Property 2
Entry and exit decisions work to ensure that labor and capital move across industries to balance production so that the greatest use is made of our limited resources.
What does a marginal cost curve look like?
When do firms enter a market?
When firms are making a profit
When should firms exit the market?
When firms are making losses, 0 profit.
Where are profits maximized?
When MC=MR