Sheridan Co. has a capital structure, based on current market values, that consists of 45 percent debt, 6 percent preferred stock, and 49 percent common stock. If the returns required by investors are 8 percent, 10 percent, and 15 percent for the debt, preferred stock, and common stock, respectively, what is Sheridans after-tax WACC? Assume that the firms marginal tax rate is 40 percent. (Round final answer to 2 decimal places, e.g. 15.25%.)

After-Tax WACC = ?%