help with 93. i figured out a) and b). i just need help with c)-e)

A) was 140,000 increase & 120,000 increase

B) was 260,000 total increase

93. The materials used by Hibiscus Company's Division A are currently purchased from an outside supplier at $55 per unit. Division B is able to supply Division A with 20,000 units at a variable cost of $42 per unit. The two divisions have recently negotiated a transfer price of $48 per unit for the 20,000 units. a. By how much will each division's income increase as a result of this transfer? b. What is the total increase in income for Hibiscus Company? c. What is the investment turnover? d. What is the rate of return on investment? e. What is Miller's residual income