Suppose that a firm's production function is given by U=K.33 * L.67, where marginal product of capital is QK = .67(K-0.67 * L.67) and MPL is QL = .67(K.33 * L-.33).
a. As L increases, what happens to the marginal product of labor?
b. As K increases, what happens to the marginal product of labor?
c. Why would the MPL change as K changes?
d. What happens to the marginal product of capital as K increases? As L increases?