Calculate the after-tax WACC for a firm with a 25 percent tax rate, a 10 percent cost

Question:

Calculate the after-tax WACC for a firm with a 25 percent tax rate, a 10 percent cost of debt, a 30 percent cost of equity, and a target debt to value of 0.30. Explain how investing to provide the WACC returns keeps the debt and equity investors happy.