please show all formulas and reasoning for this question, thank you in advance

Suppose Fox Wood Corp. (FWC) has perpetual earnings before interest and taxes (EBIT) of $10 million per year. Fox Woods unlevered cost of equity is 12%. FWC is subject to a corporate tax rate of 40%. It has $50 million in permanent debt in its capital structure, and the (pre-tax) cost of debt is 7% (EAR). What is the after-tax WACC for Fox Wood Corp?