Before and after-tax cost of debt For the following $1,000-par-value bond paying semi-annual interest payments, calculate the before- and after-tax cost of debt. Use the 21% corporate tax rate. Issuer Name ATT Inc. Coupon Rate 4.50% Years to Maturity 27 Price $1,152.14 The before-tax cost of debt for ATT Inc. is %. (Round to two decimal places.) The after-tax cost of debt for ATT Inc. is [%. (Round to two decimal places.)