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Problem 13.11 (Solution Video) Your answer is incorrect. Try again. Wildhorse Co. has a capital structure, based on current market values, that consists of 50 percent debt, 4 percent preferred stock, and 46 percent common stock. If the returns required by investors are 9 percent, 10 percent, and 15 percent for the debt, preferred stock, and common stock, respectively, what is Wildhorse's after-tax WACC? Assume that the firm's marginal tax rate is 40 percent. (Round final answer to 2 decimal places, e.g. 15.25%.) After tax WACC 9.7311 %