A profit-maximizing firm is perfectly competitive and is at long-run equilibrium. The output of the firm is 200 units and the total revenue is $1,200.00.Based on the information given, which of the following applies for the firm?
a. The firm’s marginal cost is $4.00.
b. The firm’s marginal cost is $6.00
c. The firm’s marginal cost is $700
d. The firm’s marginal cost is $9.00