6. A company is considering the purchase of a machine that costs $45,000. The machine will generate the after-tax cash flows and it will have the salvage values shown below. If the companys weighted average cost of capital is 13% per year, how long should it operate the machine?

Year Cash flow | Salvage value 25,000 15,000 10,000 5,000 30,000 20,000 10,000 5.000 3,000