BTC Inc. has the following capital structure: - 30,000 common shares outstanding. The current share price is $15 (per share), and the beta is 1.4. - 20 years to maturity, 12% coupon bonds with $150,000 par value. Currently, the bonds are trading at YTM of 7.5\%. - 15 years to maturity, 4% coupon bonds with $200,000 par value. Currently, the bonds are trading at 0.75 ( 75% of par). All bonds pay semi-annual coupons. The tax rate is 30%. The market risk premium is 9% and the risk-fre rate is 4%. a) Calculate the cost equity. b) Calculate the after-tax cost of debt. c) Calculate the WACC. d) Estimate the unlevered beta. e) Assume that BTC increases its debt-to-equity ratio to 0.9 and its cost of debt does not change, estimate its new cost of equity and WACC