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27) Suppose DFB does not have any debt now. DFB start to restructure its existing debt, and will instead pay $30 million in interest each year for the next 10 years. These payments are risk free, and DFB's marginal tax rate will remain 25% throughout this period. If the risk-free interest rate is 6%, by how much does the interest tax shield increase the value of DFB? 28) Taggart Transcontinental currently has no debt and an equity cost of capital of 16%. Suppose that Taggart decides to increase its leverage and maintain a market debt-to-value ratio of 1/3. Suppose Taggart's debt cost of capital is 9% and its corporate tax rate is 21%. Assuming that Taggart's pre-tax WACC remains constant, then with the addition of leverage its effective after-tax WACC will be