甲项目折旧=(110-15)/5=19
NCF0=-150
NCF1-4=30%2B19=49
NCF5=49%2B40%2B15=104
净现值=-150%2B49(P/A 10% 4)%2B104(P/F 10% 5)
乙项目 折旧=(130-18)/5=22.4
NCF0=-130
NCF1=0
NCF2=-50
NCF3-6=76.8*0.75%2B22.4=80
NCF7=80%2B50%2B18=148
净现值=-130-50(P/F10%1)%2B80(P/A 10% 4)(P/A 10% 2)%2B148(P/F 10% 7)