3. For the cash flows below, use an annual worth comparison to determine which alternative is best at an interest rate of 2% per month. A B First cost ($) M&O cost ($/month) Overhaul every 10 years (S) Salvage value (8) Life (years) -90,000 -400,000 -900,000 -30,000 -20,000 -13,000 -80,000 7,000 25,000 200,000 6