1. The marginal product of an input is A. total product divided by the amount of the input used to produce this amount of output. B. the addition to total output due to the addition of one unit of all other inputs. C. the addition to total output that adds nothing to total revenue. inputs constant. D. the addition to total output due to the addition of the last unit of an input, holding all other 2. In a perfectly competitive market, A. transaction costs are high. B. firms can freely enter and exit. C. firms sell a differentiated product. D. All of the above. 3. A firm will shut down in the short run if A. total revenue from operating would not cover all costs. B. total revenue from operating would not cover variable costs. C. total revenue from operating would not cover fixed costs. D. total fixed costs are too high. 4. Suppose a monopolist has TC = 40 + 10Q + Q2, and the demand curve it faces is P = 130 - 20 What is the profit-maximizing price and output? A. P = 110; Q = 40 B. P = 90; Q = 40 C. P = 90; Q = 20 D. P = 50; Q =20 5. A firm's marginal product of labor is 4 and its marginal product of capital is 5. If the firm adds one unit of labor but does not want its output quantity to change, the firm should A. add 1.25 units of capital. B. use 1.25 fewer units of capital. C. use 0.8 fewer units of capital. D. use 5 fewer units of capital