104. How does performance evaluation in investment centers differ from other centers? a) What is the formula for return on investment (ROI)? Operating income/Avg total assets b) If net sales revemes are $10,000, operating income is $2,000, average total assets are $20,000, and management's targeted rate of retum is 8%, what is the return on rivestment? I" c) Using the information in part b) above, what is the profit margin ratio? d) Using the information in part b) above, what is the asset turnover ratio? c) Using the information in part b) above, what is the residual income