We are evaluating a project that costs $837519, has an eight-year life, and has no salvage value. Assume that depreciation is straight-line to zero...

We are evaluating a project that costs $837519, has an eight-year life, and has no salvage value. Assume that depreciation is straight-line to zero over the life of the project. Sales are projected at 57519 units per year. Price per unit is $40, variable cost per unit is $18, and fixed costs are $424660 per year. The tax rate is 35%, and we require a return of 20% on this projectIn percentage terms, what is the sensitivity of NPV to changes in the units sold projection?  The answer is 2.25 but I can not figure how to get the answer