A specialty concrete mixer used in construction was purchased for \($300,000\) 7 years ago. It is MACRS-GDS 5-year property. Its annual O&M costs are \($105,000.\) At the end of an 8-year planning horizon, the mixer will have a salvage value of \($5,000.\) If the mixer is replaced, a new mixer will require an initial investment of \($375,000,\) and at the end of the 8-year planning horizon, the new mixer will have a salvage value of \($45,000.\) Its annual O&M cost will be only \($40,000\) due to newer technology. Use an EUAC measure, a tax rate of 40 percent, and an after-tax MARR of 9 percent to perform an after-tax analysis to see if the concrete mixer should be replaced if the old mixer is sold for its market value of \($65,000.

a. Use the cash flow approach (insider’s viewpoint approach). 

b. Use the opportunity cost approach (outsider’s viewpoint approach).