Q4: Machines that have the following costs are under consideration for a robotized welding process. Using an interest rate of 10% per year, determine which alternative should be selected on the basis of a present worth analysis. Show (a) hand and (b) spreadsheet solutions. Machine X Machine Y First cost, $ 250.000 430.000 Annual operating cost, $ per year - 60.000 40.000 Salvage value, $ 70,000 95.000 Life, years 3 6