Refer to Figure 12-5. What is the minimum price the firm requires to produce output?

Every time you go to the grocery store, you try to wait in the shortest line. But the lines always seem to be roughly the same length. Why?

A. Random chance equalizes the length of the lines. B. The cashiers work at the same speed. C. Other people are trying to choose the shortest line too. D. The cashiers do not have an incentive to work faster.

If MC = Q/15 represents marginal cost for a monopolist and market demand is given by Qd = 500 - 10P, the equation for marginal revenue is:

A. MR = 50 - (1/10)Q. B. MR = 50Q - (1/5)Q2. C. MR = 50Q - (1/10)Q2. D. MR = 50 - (1/5)Q.