Problem 3: Perform a differential benefit/cost (AB/C ratio) analysis to select the most economic system from the given two alternatives using i %. Alternative Initial cost Annual operating cost Annual benefits Annual disbenefits Life in years X 320 40 11 2 10 Y 540 45 17 4 20 Problem 2: For the costs shown in the table below, perform an annual worth (AW) analysis to select the most economic system. The interest rate is i% per year and the cost is thousands of dollars. (6 points) X - 90 - 40 Y - 400 - 20 System First cost Annual operating cost Update every 10 year Salvage value Life in years z - 650 - 13 F=- 80 7 3 25 10