A company has a market value of $500 million. It has a market value of equity of $200 million, a market value of long-term debt of $150 million. The cost of equity is 12%, the cost of long -term debt is 8%, and the cost of short-term debt is 6%. The marginal tax rate is 35%. What is the weighted average per-tax cost of capital (WACC) for this company? Please explain using the WACC formula. Do not use excel.