$2.$ An overview of a firm's cost of debtTo calculate the after$-$tax cost of debt, multiply the before$-$tax cost of debt by $.$Three Waters Company $($TWC$)$ can borrow funds at an interest rate of $10\mathrm{.}20\%$ for a period of four years. Its marginal federal$-$plus$-$state tax rate is $45\%.$ TWCs after$-$tax cost of debt is $($rounded to two decimal places$).$At the present time, Three Waters Company $($TWC$)$ has $20-$year noncallable bonds with a face value of $$1,000$ that are outstanding. These bonds have a current market price of $$1,181\mathrm{.}96$ per bond, carry a coupon rate of $13\%,$ and distribute annual coupon payments. The company incurs a federal$-$plus$-$state tax rate of $45\%.$ If TWC wants to issue new debt, what would be a reasonable estimate for its after$-$tax cost of debt $($rounded to two decimal places$)?5\mathrm{.}32\%5\mathrm{.}91\%7\mathrm{.}09\%6\mathrm{.}80\%$