The Nolan Corporation finds it is necessary to determine its marginal cost of capital. Nolaris current capital structure calls for 30 . percent debt, 20 percent preferred stock, and 50 percent common equity. Initially, common equity wit be in the form of fatained earnings (Ka) and then new common stock (Kn). The costs of the various sources of financing are as follows debt (after-tax) 9.7 percent; preferred stock, 8 percent; retained earnings, 9 percent, and new common stock, 102 percent. a. What is the initial welghted average cost of capital? (tnclude debt, preferred stock, and common equity in the form of retained earnings, Ke ) (Do not round intermediate calculations. Input your answers as a percent rounded to 2 decimat places) b. If the firm has $31 million in retained earnings, at what size capital structure will the firm run out of retained earnings? (Enter your answer in millions of dollars (e.9., 510 million should be entered as 10).)