The following graph depicts the costs and revenues for an unregulated monopolist: $100 MC Costs and revenues on 68 868 8388 AR 200 400 600 800 1000 1200 Quantity per period Refer to the graph above to answer this question. At what output has the firm reached economic capacity? O a. 600 O b. 975 O c. 900 O d. 800 O e. 300