The service division of Culver Industries reported the following results for 2022. Sales $580,000 Variable costs 348,000 Controllable fixed costs 72,500 Average operating assets 725,000 Management is considering the following independent courses of action in 2023 in order to maximize the return on investment for this division. 1. Reduce average operating assets by $145,000, with no change in controllable margin. 2. Increase sales $116,000, with no change in the contribution margin percentage. (a) Compute the controllable margin and the return on investment for 2022. Controllable margin Return on investment for 2022 %