Company Bourbons book value of capital is as follows: Debt $11,500,000; Pref Stock $10,000,000; Common Stock $15,200,000. The market value of Company Bourbons capital is: Debt $11,500,000; Pref Stock $22,500,000; Common Stock $35,000,000. Company Bourbons after-tax cost of debt is 5.7%, preferred stock has required return of 7.5% and common stock has a required return of 15.0%. What is Bourbons weighted average cost of capital? (Select the correct answer and show work)

a.) 9.4%

b.) 10.0%

c.) 11.0%

d.) It cannot be determined without knowing the tax rate