Suppose the market values of common stock, long-term debt, and preferred stock are $50 billion, $15 billion, and $10 billion, respectively, for Company XYZ. The pretax cost of common stock is 10%, pretax cost of debt is 8%, and the pretax cost of preferred stock is 7%. Estimate the WACC for the Company XYZ given that its effective tax rate is 25%. Show work.