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【单选题】
已知一定条件下，有下列反应（相同质量的金刚石．石墨完全反应） C(石墨)+O 2 (g)=CO 2 (g) △H=－393.5kJ/mol C(金刚石)+O 2 (g)=CO 2 (g) △H=－395.0kJ/mol 据此判断，下列说法正确的是 [ ]A.
由石墨制备金刚石是吸热反应；等质量时，石墨的能量比金刚石的低
B.
由石墨制备金刚石是吸热反应，等质量时，石墨的能量比金刚石的高
C.
由石墨制备金刚石是放热反应，等质量时，石墨的能量比金刚石的低
D.
由石墨制备金刚石是放热反应，等质量时，石墨的能量比金刚石的高
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【简答题】设随机变量X的分布律为 X 0 1 2 3 P 0.1 A 0.3 0.2 求
【简答题】设随机变量X的分布律为P{X=k}=1/4(k=1，2，3，4)，函数Y=eosπX．求二维随机变量(X，Y)的联合分布律．
【单选题】设随机变量X的分布律为 X -2 0 2 P 0.3 0.2 0.5 则Y=|X|的分布列为( )
A.
X 2 0 2 P 0.3 0.2 0.5
B.
X 0 2 P 0.2 0.8
C.
X -2 0 2 P 0.09 0.04 0.25
D.
X 0 2 P 0.04 0.14
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【多选题】Bronze ware was a unique national treasure because of ( )
A.
impressive designs
B.
classical decorative ornamentation
C.
priceless lightness
D.
wealth of inscriptions
【单选题】听力原文：M: Would you pass me the sports section，please? W: Sure, if you give me the classified ads and local news section. Q: What are the speakers doing? (19)
A.
Talking about sports.
B.
Writing up local news.
C.
Reading newspapers.
D.
Putting up advertisements.
【单选题】Passage Two
A.
The difference between classical music and rock music.
B.
Why classical music is popular with math students.
C.
The effects of music on the results of math tests.
D.
How to improve your reasoning ability.
【简答题】设随机变量X的分布律为 X 0 1 2 3 P 0.1 A 0.3 0.2 求(1)常数A；(2)P(0.5≤X＜2)．
【单选题】This passage mainly discusses _____.
A.
causal reasoning
B.
various types of reasoning
C.
classification of cause
D.
the causal process
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