A firm has $50 billion (B) of capital, including $10B of debt and $40B of equity. The debt capital consists of $2B in loans at an interest rate of 8% compounded quarterly and $8B in $1,000 10-year 5% quarterly bonds having a brokerage fee of $12 per bond. The equity capital consists of $10B in retained earnings and $30B in common stock. The firm's beta is 1.25. The risk-free interest rate is 3%. The firm bases its WACC calculation on a US equity market risk premium of 5%. Its income tax rate is 40%, what is the firm's after-tax WACC? Show your answer as a percentage to 2 decimal places.