suppose a company has 15,000 7.5% coupon bonds outstanding. These bonds have 20 years to maturity, and are selling for 109% of par. Each bond has a $1,000 par value and makes semiannual payments. If the tax rate is 32 percent, then the after tax cost of debt is

a. 4.73% b. 5.15% c. 4.54% d. 5.07% e. 4.92%