To calculate the after-tax cost of debt, multiply the before-tax cost of debt by (1-T)Y Water and Power Company (WPC) can borrow funds at an interest rate of 12.50% for a period of seven years. Its marginal federal-plus-state tax rate is 40%. WPC's after-tax cost of debt is (rounded to two decimal places) At the present time, Water and Power Company (WPC) has 20-year noncallable bonds with a face value of $1,000 that are outstanding. These bonds have a current market price of $1,382.73 per bond, carry a coupon rate of 13%, and distribute annual coupon payments. The company incurs a federal-plus-state tax rate of 40%. If WPC wants to issue new debt, what would be a reasonable estimate for its after-tax cost of debt (rounded to two decimal places)? (Note: Round your YTM rate to two decimal place.) 4.78% 6.11% 6.37% 5.31%