Targaryen Corporation has a target capital structure of 65 percent common stock, 10 percent preferred stock, and 25 percent debt. Its cost of equity is 13 percent, the cost of preferred stock is 8 percent, and the pretax cost of debt is 9 percent. The relevant tax rate is 25 percent. a. What is the companys WACC? b. What is the aftertax cost of debt?