Given the following information regarding Builtrite's capital structure, calculate its weighted average cost of capital assuming a $40\%$ tax bracket.

Type of Cost

Debt $($before tax$)$

Preferred Stock

Common Stock

Target $\%$

$30$

$10$

$60$

Cost

$9\%$

$11\%$

$16\%$

O $12\mathrm{.}32\%$

$13\mathrm{.}73\%$

O $12\mathrm{.}59\%$

$13\mathrm{.}90\%$