ABC company has a target capital structure of 30% debt, 15% preferred stock, and 55% common equity. The companys after tax cost of debt is 7%, its cost of preferred stock is 11%, its cost if retained earnings is 15% and its cost of new common stock is 16%. The company stock has a beta of 1.5 and the companys marginal tax rate is 35%. What is the companys weighted average cost of capital if retained earnings are used to fund the common equity portion?