Please find return on investment, not residual income

The Street Division of Labrosse Logistics just started operations. It purchased depreciable assets costing $36 million and having a four-year expected life, after which the assets can be salvaged for $7.2 million. In addition, the division has $36 million in assets that are not depreciable. After four years, the division will have $36 million available from these non depreciable assets. This means that the division has invested $72 million in assets with a salvage value of $43.2 million. Annual operating cash flows are $12 million. In computing ROI, this division uses beginning-of-year asset values in the denominator. Depreciation is computed on a straight-line basis, recognizing the salvage values noted. Ignore taxes. Required: a. \& b. Compute ROI, using net book value and gross book value. Note: Enter your answers as a percentage rounded to 2 decimal place (i.e., 32.10)