Aphid Corp. will finance its next major expansion with $60\%$ debt, $10\%$ preferred stock, and $30\%$ retained earnings. Aphid$$s after$-$tax cost of debt is $5\mathrm{.}1\%,$ cost of preferred stock is $8\mathrm{.}6\%,$ and cost of retained earnings is $13\mathrm{.}5\%.$ What is the corporation$$s weighted average cost of capital? Submit your answer as a percentage and round to two decimal places $($Ex$.0\mathrm{.}00\%)$