The Central Division of National Inc. has operating income of $18,700 on sales revenue of $197,000. Divisional operating assets are $81,300, and management of National has determined that a minimum return of 14% should be expected from all investments. Required: a. Using the DuPont model, calculate the Central Division's margin, turnover, and ROI. (Do not round Intermediate calculations. Round your answers to 2 decimal places.) Margin Turnover ROI Central Division % turns % b. Calculate the Central Division's residual Income. Residual income