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Question 4 (4 points) Individual firms in perfect competition are price takers because firms decide together on the best price to charge. buyers set prices. the government sets all prices. each firm is too small to affect the market price. Question 12 (4 points) A perfectly competitive firm shuts down in the short run if the price of its product is greater than its maximum average variable cost. less than its minimum average variable cost. less than its minimum average total cost. greater than its minimum average variable cost. Question 18 (4 points) For a monoplist to sell one more unit of a good it must raise the price on just the last unit sold. lower the price on just the last unit sold. lower the price on all units sold. raise the price on all units sold