相關Heb的文學知識

問題詳情：Acollegeteacheroncegavealivelyclasstohisstudents．   Hebeganbyholdingupaglass（1）somewaterinit．Hehelditupforalltosee，andaskedthestudents，"（2）doyouthinkthisglassweighs？"   "50g!""100g!""125g!...