2.Explain how the counterweight help us save energy.
please explain briefly. THX A LOT ^^
更新1:
2 IS ABOUT ELEVATOR COUNTERWEIGHT SYSTEM
2 IS ABOUT ELEVATOR COUNTERWEIGHT SYSTEM
收錄日期: 2021-04-29 17:39:09
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20110212000051KK01385