The after-tax cost of debt for purposes of estimating a company's weighted-average cost of capital (WACC 20 Multiple Choice is equal to the pretax cost of debt(1-0. where t= income tax rate. Requires an estimate of the yield-to-maturity for long-term bonds Is approximated by the firm's short-term borrowing rate. Is equal to the pretax cost of debt times t,where tincome tax rate. Is estimated using the Capital Asset Pricing Model (CAPM)