The South Division of Wiig Company reported the following data for the current year. Top management is unhappy with the investment center's return on investment (ROI). It asks the manager of the South Division to submit plans to improve ROI in the next year. The manager believes it is feasible to consider the following independent courses of action. Increase sales by $320,000 with no change in the contribution margin percentage. Reduce variable costs by $151, 500. Reduce average operating assets by 3%. (a) Compute the return on investment (ROI) for the current year. (b) Using the ROI formula, compute the ROI under each of the proposed courses of action