风湿性心脏瓣膜病的中医病名是（） A.心悸 B.怔忡 C.心痹 D.胸痹 E.心痛

超声换能器可以（）

A.变机械能为声能

B.电能与机械能互变

C.变热能为声能

D.变任意能为电能

E.变电能为热能

铁是在_________条件下最易生锈，将一枚锈铁钉放入足量的稀硫酸中，依次观察到的现象______________。有关化学方程式为__________________。

看图填词，每空不限一词。

1. Monday is hot but Tuesday is _____ than Monday.

2. The diamond ring (钻戒) is expensive, but the watch is _____ it.

3. _____ is _____ than Tony.

4. The orange is _____ of the three kinds of fruit.

5. Peter is angry but Mary is _____.

监测光缆金属护套对地绝缘和电位在光缆的接头处应选用监测标石。

信托