文物是鲜活的历史。下列文物中最能反映商朝社会生活的是
A.兵马俑
B.司母戊鼎
C.竹木简
D.青花瓷
答案:B
---Waiter, $ 20 for dinner, right?
--- I’m afraid $ 25, sir, for drinks are ________.
A.free
B.extra
C.high
D.spare
减温器有哪几种型式?优点如何?