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If barriers to entry or product differentiation competition in a market will O increase; increases; decrease increase; increases; increase increase; decreases; increase O decrease; increases; increase O decrease; decreases; decrease Question 21(Multiple Choice Worth 1 points) (03.07 MC) What is true of a firm's production if it operates in a perfectly competitive market in long-run equilibrium? O Marginal revenue = demand = marginal cost > average total cost O Marginal revenue = marginal cost = average fixed cost O Average total cost = price = average variable cost O Marginal cost