A manufacturer of hydraulic equipment is trying to determine whether it should use monofl ange double block and bleed (DBB) valves or a multi-valve system (MVS) for chemical injection. The costs are shown below. Use an AW-based rate of return analysis and a MARR of 18% per year to determine the better of the two options. DBB MVS First cost, $ 40,000 71,000 Annual cost, $ per year 60,000 65,000 Salvage value, $ 0 18,000 Life, years 2 4