Assume that your company is trying to determine its optimal capital structure, which consists only of debt and common stock. To estimate the cost of debt, the company has produced the following table:

$\backslash$table$[[\backslash$table$[[$Percent Financed$],[$With Debt$]],\backslash$table$[[$Percent Financed$],[$With Equity$]],\backslash$table$[[$Debt$/$Equity$],[$Ratio$]],\backslash$table$[[$Bond$],[$Rating$]],\backslash$table$[[$Before$-$Tax$],[$Cost of Debt$]]],[0\mathrm{.}10,0\mathrm{.}90,\frac{0\mathrm{.}10}{0\mathrm{.}90}=0\mathrm{.}11,$AA$,7\mathrm{.}0\%$