Rogot Instruments makes fine violins and cellos. It has $$$$1\mathrm{.}3$ million in debt$$ outstanding, equity valued at $$$$2\mathrm{.}8$ million and pays corporate income tax at rate $21\%.$ Its cost of equity is $12\%$ and its cost of debt is $6\%.$

If the pretax WACC is $10\mathrm{.}10\%,$ what is the effective after tax WACC?

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