National Homebuilders, Inc, plans to purchase new cut-and-finish equipment. Two manufac- turers offered the estimates below. First cost, $ Annual M&O cost, $ per year Salvage value, $ Life, years Vendor A -15,000 - 3,500 1,000 Vendor B -18,000 -3.100 2,000 (@) Determine which vendor should be selected on the basis of a present worth comparison, if the MARR is 15% per year. (b) National Homebuilders has a standard practice of evaluating all options over a 5-year period. If a study period of 5 years is used and the salvage values are not expected to change, which vendor should be selected