You were hired as a consultant to Quigley Company, whose target capital structure is 20% debt, 10% preferred, and 70% common equity. The interest rate on new debt is 8.00%, the yield on the preferred is 6.00%, the cost of retained earnings is 9.75%, and the tax rate is 25%. The firm will not be issuing any new stock. What is Quigley's WACC? Round final answer to two decimal places. Do not round your intermediate calculations. a. 8.03% b. 6.77%