The Central Division of National Inc. has operating income of $18,700 on sales revenue of $155,000. Divisional operating assets are $80,300, and management of National has determined that a minimum return of 11% 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 Turnover % turns ROI % b. Calculate the Central Division's residual income. Residual income