问题
选择题
---May I use your dictionary? I need to look up a word.
---It’s over there. _______. [ ]
A. It depends
B. Got it
C. Feel free
D. No problem
答案
答案:C
---May I use your dictionary? I need to look up a word.
---It’s over there. _______. [ ]
A. It depends
B. Got it
C. Feel free
D. No problem
答案:C
家用瓶装液化石油气主要成份是烷烃和烯烃系列的混合物,在一标准大气压下各成份的沸点如下表所示.常温下液化石油气很难用尽,瓶内常有残留物.该残留物的主要成份是( )
物质名称 | 甲烷 | 乙烷 | 丙烷 | 丁烷 | 戊烷 | 乙烯 | 丙烯 | 丁烯 | 戊烯 |
沸点(℃) | -161.7 | -88.6 | -42.2 | -0.5 | 36.1 | -102.4 | -47.7 | -6.5 | 30.1 |
A.甲烷 乙烯
B.丁烷 丁烯
C.戊烷 戊烯
D.丙烷 丙烯