折旧=(63-3)/5=12NCF0=-63NCF1~4=(55-10)×0.8+12×0.2=38.4NCF5=38.4+3=`41.4NPV=-63+38.4×(P/A,15%,4)+41.4×(P/F,15%,5)=67.21PI=1+67.21/63=2.07该项目可行
