You were hired as a consultant to Giambono Company, whose target capital structure is 45% debt, 15% preferred, and 40% common equity. The after-tax cost of debt is 6.00%, the cost of preferred is 8.50%, and the cost of retained earnings is 12.00%. The firm will not be issuing any new stock. What is its WACC? a. 6.08% b. 3.98% c. 8.78% d. 7.50% e. 8.83%