4. If the marginal product of labor is 100 and the price of labor is 10, while the marginal product of capital is 200 and the price of capital is $30, then what should the firm? a. The firm should use relatively more capital b. The firm should use relatively more labor C. The firm should not make any changes -they are currently efficient d. Using the Equimarginal Criterion, we can't determine the firm's efficiency level e. Both c and d