Olsen Outfitters Inc. believes that its optimal capital structure consists of $60\%$ common equity and $40\%$ debt, and its tax rate is $25\%.$ Olsen must raise additional capital to fund its upcoming expansion. The firm will have $$2$ million of retained earnings with a cost of rs $=11\%.$ New common stock in an amount up to $$9$ million would have a cost of re $=13\mathrm{.}0\%.$ Furthermore, Olsen can raise up to $$4$ million of debt at an interest rate of rd $=9\%$ and an additional $$4$ million of debt at rd $=13\%.$ The CFO estimates that a proposed expansion would require an investment of $$7\mathrm{.}4$ million. What is the WACC for the last dollar raised to complete the expansion? Round your answer to two decimal places.

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