The Alpha Corporation is a member of the lamp industry, which is perfectly competitive. The value of a lamp is $50. The company's total cost function is:
TC = 1,000 + 20Q +5Q²
Where TC is the total cost (in dollars) and Q is hourly output.
a. What output maximizes profit?
b. What is the firm's economic profit at this output?
c. What is the firm's average cost at this output?
d. If the other firms in the lamp industry have the same cost function as this firm, is the industry in long-run equilibrium? Why or why not?