Pfd Company has debt with a yield to maturity of 7.5%, a cost of equity of 12.9%, and a cost of preferred stock of 9.2%. The market values of its debt, preferred stock, and equity are $13.2 million, $3.2 million, and $16.9 million, respectively, and its tax rate is 35%. What is this firm's after-tax WACC? Note: Assume that the firm will always be able to utilize its full interest tax shield