Pfd Company has debt with a yield to maturity of 7.8%, a cost of equity of 13.5%, and a cost of preferred stock of 9.4%. The market values of its debt, preferred stock, and equity are $14.2 million, $2.8 million, and $15.9 million, respectively, and its tax rate is 25%. What is this firm's after-tax WACC? Note: Assume that the firm will always be able to utilize its full interest tax shield. Pfd's WACC is \%. (Round to two decimal places.)