问题
单项选择题
下列燃气燃烧后高低热值等(或无高低热值之分)的气体有()。
A.氢气
B.甲烷
C.一氧化碳
D.乙烷
答案
参考答案:C
下列燃气燃烧后高低热值等(或无高低热值之分)的气体有()。
A.氢气
B.甲烷
C.一氧化碳
D.乙烷
参考答案:C
附加题(10分) 小题1: —How long may I _________ the book? —Two weeks.
小题5: ______ always do the __________ exercises after watching TV. Use the words below to complete the following sentences.
Nobody can 小题6:________ happy all the time. You may become 小题7:________ sometimes, for example, when you fail an exam; or you may become 小题8:________ when you lose one of your 小题9:_________. It’s normal to have these feelings. If you don’t know how to deal with these 小题10:___________, you may learn something from Jeff. |