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The Beta Corporation has an optimal debt ratio of 40 percent. Its cost of equity capital is 12 percent and its before-tax borrowing rate is 10 percent. Given a marginal tax rate of 30 percent. a. Calculate the weighted-average cost of capital. (Do not round Intermediate calculations. Round your answer as a percent rounded to 2 decimal places.) Answer is complete but not entirely correct. Weighted-average cost of capital 10.79 % b. Calculate the cost of equity for an equivalent all-equity financed firm. (Do not round Intermediate calculations, Round your answer as a percent rounded to 2 decimal places.) Answer is complete but not entirely correct. Cost of equity 9.28 2