Westerville Company reported the following results from last year's operations: Sales $ 1, 500,900 Variable expenses 730,000 Contribution margin 770,900 Fixed expenses 470,000 Net operating income $ 300, 900 Average operating assets $ 937, 500 At the beginning of this year, the company has a $362,500 investment opportunity with the following cost and revenue characteristics: Sales $ 580,000 Contribution margin ratio 70 % of sales Fixed expenses $ 319,000 The company's minimum required rate of return is 10%. 3. What is last year's return on investment (ROI)