Shirley's and Son have a debt-equity ratio of .60 and a tax rate of 35 percent. The firm does not issue preferred stock. The cost of equity is 10 percent and the pre-tax cost of debt is 8 percent. What is Shirley's weighted average cost of capital? A. 6.1 percent B.8.2 percent C 8.4 percent D.9.1 percent E. 9.4 percent