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Three stamping machines are under consideration for purchase by a metal recycling company. The manual model will cost $18,000 to buy with a 4 -year life and a salvage value of $2000. A semi-automated machine will cost $25,000 with a 5-year life and a salvage value of $5,000. A computer-controlled model will cost $35,000 to buy and it will have a 7-year life with a salvage value of $14,000. Their plan is to analyze all the machines with a 10 year analysis period. They assume the machines rate of depreciation over the course of their useful life is linear. Using present worth analysis with a minimum attractive rate of return of 10%, which of the machines should the company buy