负压气力输灰系统的空气加热全部采用蒸汽加热方式。()
参考答案:错
用所给单词的适当形式填空。
l. Mr Brown _____ (go) to his office by bike every day.
2. Why not _____ (go) to the zoo by bus?
3. It ____ (take) about 15 minutes to walk.
4. There _____ (be) many deer in the forest now.
5. There must _____ (be) many sheep.
6. Kate is walking to her home ____ (quick).
对质量相等的100℃的水和100℃的水蒸气,以下说法正确的是:( )
A.水分子势能比水蒸气分子势能大
B.水蒸气分子势能与水分子势能一样大
C.它们的分子平均动能相同,内能却不同
D.它们的分子平均动能不同,内能也不同