why DoEs thE proFEssor CitE gtE、AirFonE As An ExAmplE
A、to illustrAtE how plACE utility is CrEAtED、
B、to illustrAtE how timE utility is CrEAtED、
C、to illustrAtE how ownErship utility is CrEAtED、
D、to illustrAtE how thE ABovE thrEE utilitiEs ArE CrEAtED、