Omega Inc. has a target debt$$equity ratio of $0\mathrm{.}78.$ Its WACC is $9\mathrm{.}9\%,$ and the tax rate is $35\%.$

a$.$ If the company$$s cost of equity is $14\%,$ what is its pre$-$tax cost of debt?

b$.$ If instead you know that the after$-$tax cost of debt is $6\mathrm{.}8\%,$ what is the cost of equity?