Butler, Inc., has a target debt$-$equity ratio of $1\mathrm{.}55.$ Its WACC is $9\mathrm{.}8$ percent, and the tax rate is $21$ percent.

a$.$ If the company's cost of equity is $13\mathrm{.}6$ percent, what is its pretax cost of debt? $($Do not round intermediate calculations and enter your answer as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

b$.$ If instead you know that the aftertax cost of debt is $6\mathrm{.}8$ percent, what is the cost of equity? $($Do not round intermediate calculations and enter your answer as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

$\backslash$table$[[,],[$a$.,$Pretax cost of debt,,$\%$