A. at the efficient scale and charge a price equal to marginal cost
B. at the efficient scale and charge a price above marginal cost
C. With excess capacity and charge a price above marginal cost
D. With excess capacity and charge a price equal to marginal cost

A. marginal revenue and then use the demand curve to determine the price consistent with this quantity
B. average total cost and then use the supply curve to determine the price consistent with this quantity
C. marginal revenue and then use the supply curve to determine the price consistent with this quantity
D. average total cost and then use the demand curve to determine the price consistent with this quantity

A. the monopolist faces a downward-slog demand curve while the monopolistic competitor faces an elastic demand curve
B. the monopolist charges a price above marginal cost while the monopolistic competitor charges a price equal to marginal cost
C. The monopolist makes economic profits in the long run while the monopolistic competitor makes zero economic profits in the long run
D. Both the monopolist and the monopolistic competitor operate at the efficient scale

A. free entry and exit
B. long run economic profits
C. many sellers
D. differentiated products