The Two Dollar Store has a cost of equity of $10\mathrm{.}8$ percent, the YTM on the company's bonds is $5\mathrm{.}4$ percent, and the tax rate is $21$ percent. If the company's debt$-$equity ratio is$\mathrm{.}43,$ what is the weighted average cost of capital?

$5\mathrm{.}70\%$

$8\mathrm{.}12\%$

$7\mathrm{.}44\%$

$9\mathrm{.}18\%$

$8\mathrm{.}84\%$