You were hired as a consultant to Quigley Company, whose target capital structure is 40% debt, 10% preferred, and 50% common equity. The interest rate on new debt is 5.50%, the yield on the preferred is 6.00%, the cost of retained earnings is 12.50%, 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. 8.50%

b. 6.79%

c. 7.54%

d. 9.05%

e. 7.90%