a. 5. A firm has a profit margin of 15 percent on sales of $20,000,000. If the firm has debt of $7,500,000, total assets of $22,500,000, and an after-tax interest cost on total debt of 5 percent, what is the firm's ROA? (This would be a problem on the exam - not a multiple choice question.) 8.4% b. 10.9% 12.0% d. 13.3% 15.1% C. e