Answer these

The table below shows present worth calculations of the costs associated with using a presently owned machine ( defender) and a possible replace- ment (challenger) for different numbers of years. Determine when the defender should be replaced using an interest rate of 10%% per year and a 3-year study period. Show solutions (a) by hand and (b) by spreadsheet. FW If Kept/Used Stated Number of Years Number of Years, $ Kept/Used Defender Challenger -36,000 -84,DO0 -75,DO0 -96,000 -125,00D - 102,DO0 -166,000 -217,DOD -149,000\f\f\f\f