Question 16 (4 points) Economic efficiency occurs when the firm produces a given output at the least cost. by using the least amount of inputs. O by using the maximum amount of inputs. at the greatest cost. Question 21 (4 points) When the marginal product equals the average product, the marginal product is at its maximum. average product is at its maximum. average product curve is downward sloping. marginal product curve is upward sloping. Question 22 (4 points) A firm has fixed costs in the long run but not in the short run. in the short run and in the long run. neither in the long run nor in the short run. in the short run but not in the long run. Question 25 (4 points) As output increases, average fixed cost decreases, then increases. always decreases. increases, then decreases. remains constant. Question 26 (4 points) When marginal cost is greater than average total cost, the marginal cost decreases as output increases. average total cost increases as output increases. average total cost decreases as output increases. marginal cost does not change as output increases