= Price MC /ATC $1.00 $0.95 $0.85 $0.60. D 300 500 900 1000 Quantity The monopolistically competitive firm represented in the graph above is in: O both short-run and long-run equilibrium because price exceeds average total cost at the profit-maximizing output level. O both short-run and long-run equilibrium because price equals marginal cost at the profit-maximizing output level. O short-run equilibrium because price exceeds average total cost at the profit-maximizing output level. O long-run equilibrium because economic profits are zero at the profit-maximizing output level