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Washington Mill Works is considering purchasing a large resawing band saw for $30,000. The saw has a useful life estimated to be seven years, at which point it will have an estimated salvage value of $8,000. Annual income each year for the 7 years is $9000. Annual operating expenses are $3.000. What is the present worth? Assume MARR = 7.5% and the planning horizon is 7 years. what is the annual worth? what is the future worth? what is the internal rate of return. what is the external rate of return