Thelifeexpectancyisthelengthoftimethatapersonisnormally...
問題詳情:Thelifeexpectancyisthelengthoftimethatapersonisnormallylikelytolive.Asitincreasesnowadays,theAveragepersonlivesbeyondtheageofretirement.Asaresult,theelderlymakeupanever-increasingpercentageofs...