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【单选题】
下列5种烃:12-甲基丙烷;2乙烷;3丙烷;4丁烷;5。按它们的沸点由高到低的顺序排列正确的是()。A.
①②③④⑤
B.
⑤④①③②
C.
④⑤②①③
D.
③①②⑤④
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【单选题】支柱金属支柱基础面应高出地面（或站台面）100－200mm。基础外露400mm以上者应培土，每边培土宽度为500mm，培土边坡与水平面成（）。
A.
15°
B.
25°
C.
35°
D.
45°
【单选题】根据材料，回答题。 Stars in Their Eyes The ScientifiC．American Book of the Cosmos edited by David Levy， Macmillan， 20， ISBN 0333782933 Previous generations of scientists would have killed to know what we know....
A.
Tegmark fears he may hold the record for the longest time taken to read one book.
B.
In a more positive vein， this is a wonderful collection of essays to dip in and out of if you already have a good overview （概述） of current cosmiC．understanding.
C.
Levy is an active astronomer and an accomplished writer， so you'd expect him to provide a broad and accurate picture of our current understanding of the cosmos.
D.
ScientifiC．American has attempted to cater to this need by bringing together essays that have appeared in the magazine.
E.
To some extent， these could have been plugged with a glossary （词表） of terms.
F.
Also included are contributions on the world of subatomiC．particles， the origin of life on the Earth and the possibility of its existence elsewhere.
【简答题】支柱基础面要高出地面100mm至200mm，基础外缘外露400mm以上时要进行培土，每边培土的宽度为（）mm，培土边坡与水平面成（）；基础根部不许有积水、泥土、碎石和灰渣等物。
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