$ Indicate whether each of the following statements are true or false. Explain your answers. CE DFDDE DOFDORIDOR DER DONDE 12a) The demand for Mr. Chef's pizza has a price elasticity of -4. In order to increase revenue, Mr. Chef should increase the price of pizza. CIDO 12b) At the profit-maximising output level, wage rate equals the marginal product of labor. 12c) The price of input X is $50 and the price of input Y is $20. If the marginal product of X is 10, and the marginal product of Y is 4, then the input mix of X and Y is optimal