a. A new operating system for an existing machine is expected to cost $710,000 and have a useful life of six years. The system yields an incremental after-tax income of $215.000 each year after deducting its straight-line depreciation. The predicted salvage value of the system is $26,600. b. A machine costs $550,000, has a $21,500 salvage value, is expected to last eight years, and will generate an after-tax income of $78.000 per year after straight-line depreciation. Assume the company requires a 12% rate of return on its investments, Compute the net present value of each potential investment. (PV of $1. EV of $1. PVA of $1. and EVA of S1) (Use appropriate factor(s) from the tables provided.)