16. An all-equity firm has a cost of capital of 12.8 percent and a tax rate of 23 percent. At the firm's target debt-equity ratio, the pretax cost of debt is 7.35 percent and the cost of equity is 15.07 percent. What is the target debt-equity ratio? (a) (b) (c) (d) 0.67 0.49 0.51 0.54