Bartlett Company's target capital structure is $40\%$ debt, $15\%$ preferred, and $45\%$ common equity. The before$-$tax cost of debt is $10\mathrm{.}00\%,$ the cost of preferred is $7\mathrm{.}50\%,$ and the cost of common using reinvested earnings is $12\mathrm{.}75\%.$ The tax is $40\%.$ The firm will not be issuing any new stock. You were hired as a consultant to help determine their cost of capital. What is its WACC?

Group of answer choices

$9\mathrm{.}26\%$

$8\mathrm{.}75\%$

$8\mathrm{.}30\%$

$10\mathrm{.}12\%$