For the cash flows below, use an annual worth comparison to determine which alternative is best at an interest rate of 1% per month.

X Y Z First cost, $ 90,000 400,000 900,000 M&O costs, $/month 30,000 20,000 13,000 Overhaul every 10 years, $ — — 80,000 Salvage value, $ 7000 25,000 200,000 Life, years 3 10