b. If the firm has $28 million in retained earnings, at what size capital structure will the firm run out of retained earnings? Note: Enter your answer in millions of dollars (e.g., $10 million should be entered as "10"). Capital structure size (X) c. What will the marginal cost of capital be immediately after that point? (Equity will remain at 40 percent of the capital structure, but will all be in the form of new common stock, Kn.) Note: Do not round intermediate calculations. Input your answer as a percent rounded to 2 decimal places. Marginal cost of capital million % Capital structure size (Z) d. The 6.2 percent cost of debt referred to earlier applies only to the first $42 million of debt. After that, the cost of debt will be 8.2 percent. At what size capital structure will there be a change in the cost of debt? Note: Enter your answer in millions of dollars (e.g., $10 million should be entered as "10"). million e. What will the marginal cost of capital be immediately after that point? (Consider the fac