2) A company has invested $60,000 in machinery with a 5-year useful life. The machinery will have no salvage value, as the cost to remove it will equal its scrap value. The annual benefits from the machinery are $15,000. The firm has a tax rate of 45% and will use the sum-of-years.. digits depreciation, compute the after-tax rate of return. The company uses a MARR of 7%. 2) A company has invested $60,000 in machinery with a 5-year useful life. The machinery will have no salvage value, as the cost to remove it will equal its scrap value. The annual benefits from the machinery are $15,000. The firm has a tax rate of 45% and will use the sum-of-years.. digits depreciation, compute the after-tax rate of return. The company uses a MARR of 7%