A company wants to replace old machine by new one. Old is fully depreciated and no salvage value is expected. New will provide annual cash saving by $7.000 before income taxes and without regard to the effect of depreciation. Machine (new) costs $18.000 , estimated useful life is 5 years. No salvage value will be for the n ew one. Straight line depreciation method will be used. Income tax is %40. Desired rate of return is %14. Please evaluate this investment in terms of NPV, IRR and Payback period methods.