- A company is considering purchasing a new machine and has to choose between two options. The specifications of each are given below. Both machines have 5 years economic life and the tax rate is 50%. Suppose that no tax is paid if the taxable income is non-positive. Given that after-tax MARR is 30%, determine which machine to be selected. Machine 1 Machine II First Cost ($) -90,000 Annual Revenues ($) 20,000 Depreciation Method Straight Line Salvage Value ($) 10,000 -80.000 25,000 Double Declining Balance 15.000