a. Given the following, determine the firm's optimal capital structure: Round your answers for capital structure to the nearest whole number and for the cost of capital to one decimal place. The optimal capital structure: % debt and % equity with a cost of capital of % b. If the firm were using 50 percent debt and 50 percent equity, what would that tell you about the firm's use of financial leverage Round your answer for the cost of capital to one decimal place. If the firm uses 50% debt financing, it would be using financial leverage. At that combination the cost of capital is %. The firm could lower the cost of capital by substituting