Twitter has a capital structure that is 30% debt, 10% preferred stock, and 60% common stock. Their YTM on debt is 6.25% and their tax rate is 20%. Their cost of preferred stock is 8%, and their cost of common stock is 10%. Their Weighted Average Cost of Capital (WACC) is _________________________%.

Round your answer to three decimal places. Do not include the percent symbol in your answer.