The Central Division of National Inc. has operating income of $17,800 on sales revenue of $163.000. Divisional operating assets are $82,000, and management of National has determined that a minimum return of 13% 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.) Central Division % Margin Tumover ROI tums % b. Calculate the Central Division's residual income Residual income