Ralston Company has operating income of $75,000, invested assets of $360,000, and sales of $790,000. Required: Use the DuPont formula to compute the return on investment (ROI), and show (a) the profit margin, (b) the investment turnover, and (c) the return on investment. Round the profit margin percentage to two decimal places, the investment turnover to three decimal places, and the return on investment to two decimal places. a. Profit Margin b. Investment Turnover C. Return on Investment