The Street Division of Labrosse Logistics just started operations. It purchased depreciable assets costing $$40\mathrm{.}5$ million and having a four$-$year expected life, after which the assets can be salvaged for $$8\mathrm{.}1$ million. In addition, the division has $$40\mathrm{.}5$ million in assets that are not depreciable. After four years, the division will have $$40\mathrm{.}5$ million available from these non depreciable assets. This means that the division has invested $$81$ million in assets with a salvage value of $$48\mathrm{.}6$ million. Annual operating cash flows are $$12\mathrm{.}9$ 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$.,32\mathrm{.}10).$