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Corinthian Corporation, a firm that is currently over levered with a debt to capital ratio of 70% and a pre-tax cost of debt of 7%, is considering a restructuring that will reduce its debt to capital ratio to 40% and its pre-tax cost of debt to 6%. Current Recapitalized Debt/(Debt + Equity) 70% 40% Cost of debt (Pre-tax) 7% 5% Cost of equity 22% If the marginal tax rate is 25%, the risk free rate is 2.5% and the equity risk premium is 6%, estimate the cost of capital after the restructuring. O a. 9.38% O b. 12.14% O c. 6.56% O d. 8.22%