A firm produces a product in a competitive industry and has a total cost function C =

Question:

A firm produces a product in a competitive industry and has a total cost function C = 50 + 4q + 2q2 and a marginal cost function MC = 4 + 4q. At the given market price of $20, the firm is producing 5 units of output. Is the firm maximizing its profit? What quantity of output should the firm produce in the long run?