Wentworth's Five and Dime Store has a cost of equity of $12\mathrm{.}7$ percent. The company has an aftertax cost of debt of $4\mathrm{.}4$ percent, and the tax rate is $23$ percent. If the company's debt$-$equity ratio is $\mathrm{.}87,$ what is the weighted average cost of capital?

Multiple Choice

$7\mathrm{.}26\%$

$8\mathrm{.}37\%$

$6\mathrm{.}66\%$

$8\mathrm{.}84\%$

$7\mathrm{.}72\%$