Faust Corporation is contemplating the purchase of a new $791,000 machine with a useful life of seven years for tax purposes. However, Faust plans to use the machine for only five years, after which time it expects to sell the machine for $60,000. Faust expects that the machine will be able to save $340,000 per year in operating costs over its five-year useful life. However, Faust is not certain about the income tax rates that will be in effect during the five-year useful life of this machine and, consequently, is not sure which depreciation method it should use for the machine. In calculating annual depreciation, Faust will use a salvage value of zero and a full year's deprecia- tion in both the first and last years. Faust's MARR is 14%. Required: a. Assuming that marginal combined (state and federal) income tax rates remain at 30% for the entire holding period, determine the net present value this opportunity for both straight-line depreciation and sum-of-the-years' digits depreciation. Which is the better choice? b. Assuming that marginal combined (state and federal) income tax rates remain at 30% for the first two years and then increase to 40% for the final three years of the holding period, determine the net present value this opportunity for both straight-line depreciation and sum-of-the-years' digits depre- ciation. Which is the better choice? c. Assuming that marginal combined (state and federal) income tax rates begin remain at 30% for the first two years and then decrease to 25% for the final three years of the holding period, determine the net present value this opportunity for both straight-line depreciation and sum-of-the-years' digits depreciation. Which is the better choice