Marginal Incorporated $($MI$)$ has determined that its before$-$tax cost of debt is $5\mathrm{.}0\%$ for the first $$25$ million in bonds it issues, and $9\mathrm{.}0\%$ for any bonds issued above $$25$ million. Its cost of preferred stock is $13\mathrm{.}0\%.$ Its cost of internal equity is $16\mathrm{.}0\%,$ and its cost of external equity is $18\mathrm{.}0\%.$ Currently, the firm's capital structure has $$410$ million of debt, $$80$ million of preferred stock, and $$510$ million of common equity. The firm's marginal tax rate is $45\%.$ The firm's managers have determined that the firm should have $$53$ million available from retained earnings for investment purposes next period. What is the firm's marginal cost of capital at a total investment level of $$83$ million?

Group of answer choices

$10\mathrm{.}33\%$

$12\mathrm{.}25\%$

$11\mathrm{.}23\%$

$11\mathrm{.}35\%$

$13\mathrm{.}91\%$

$12\mathrm{.}89\%$

$11\mathrm{.}45\%$

$12\mathrm{.}27\%$