You were hired as a consultant to Giambono Company, whose target capital structure is 40% debt, 15% preferred, and 45% common equity. The after-tax cost of debt is 6.00%, the cost of preferred is 7.50%, and the cost of retained earnings is 12.75%. The firm will not be issuing any new stock. What is its WACC? Select one: a. 8.98% b. 9.26% c. 9.54% d. 9.83% e. 10.12%