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Use the information to answer the following questions. The Global Advertising Company has a marginal tax rate of 30%. The company can raise debt at a 10% interest rate. The last dividend paid by Global was $2. Global's common stock is selling for $20 per share, and its expected growth rate in earnings and dividends is 8%. Global plans to finance all capital expenditures with 20% debt and 80% equity. What is the firm's weighted average cost of capital if the firm has sufficient retained earnings to fund the equity portion of its capital budget? Select one: O a. 11.59% O b. 13.95% Oc. 15.70% O d. 12.37% O e. 16.44%