the table below shows the marginal revenue and costs for a monopolist. demand, costs, and revenues price (dollars) quantity demanded marginal revenue (dollars) marginal cost (dollars) average total cost (dollars) $130 200 $110 $25 $139.00 120 300 90 32 103.30 110 400 70 40 87.50 100 500 50 50 80.00 90 600 30 62 77.00 80 700 10 77 77.00 what is the monopolist's profit at the profit-maximizing level of output? multiple choice $80,000 $0 $10,000 $50,000