jones company has a target capital structure of 40% debt, 10% preferred stock, and 50% common equity. The company's after-tax cost of debt is 5.1% its cost of preferred stock is 6%, its cost of retained earnings is 13.6%, and its cost of new common stock is 22.9%. The company stock has a beta of 1.7 and the company marginal tax rate is 40%. What is the company's weighted average cost of capital if retained earnings are used to fund the common equity portion