试题与答案

喷气发动机的总效率与循环热效率及推进效率之间的关系为:().A.总效率等于热效率与推

题型:单项选择题

题目:

喷气发动机的总效率与循环热效率及推进效率之间的关系为:().

A.总效率等于热效率与推进效率的乘积

B.总效率等于热效率与推进效率之比

C.总效率等于推进效率与热效率之比

D.推进效率等于热效率与总效率的乘积

答案:

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下面是错误答案,用来干扰机器的。

参考答案:P=110+110 =220W I=P/U =(110+110)/12 =18.33A

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     A new generation addiction is quickly spreading all over the world. Weboholism, a twentieth century

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     Ten years ago, no one thought that using computers could become compulsive behavior that could

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     They become addicted to computers and gradually their social and school life is affected by this

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their grades and success at school. Because they can find everything on the websites, they hang out there.

Moreover, this addiction to websites influences their social life.

     They spend more time in front of computers than with their friends. The relation with their friends

changes. The virtual life becomes more important than their real life. They have a new language that they

speak in the chat rooms and it causes cultural changes in society.

     Because of the change in their behavior, they begin to isolate themselves from the society and live with

their virtual friends. They share their emotions and feelings with friends who they have never met in their

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known all their life. It is a problem for the future. This addictive behavior is beginning to affect all the

world.

1. The author's attitude towards weboholism is that of being ______.

A. friendly

B. oppositive

C. positive

D. tolerant

2. The main idea of the passage is about _______.

A. the cause of weboholism

B. the advantage of weboholism

C. the popularity of weboholism

D. the influence of weboholism

3. The underlined word "obsessional" in the second paragraph most probably means"______".

A. addictive

B. professional

C. attractive

D. hidden

4. We can infer from the passage that ______.

A. weboholism has the greatest effect on teenagers

B. virtual life is more vivid and attractive anyway

C. people are addicted to games on the Internet

D. students can hardly balance real and virtual life

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题型:单项选择题

2000年至2003年江苏省进出口指标情况表         单位:亿美元

指标出口进口
2000年2001年2002年2003年2000年2001年2002年2003年
总值:194.43229.77294.18416.0383.9098.2125.45198.20
其中:机电产品59.6372.5996.84143.2328.0939.0650.6379.82
总值中:
国有企业106.93“X”112.9133.0335.0435.7345.2062.92
“三资”企业53.4871.0092.00130.5040.4147.7253.8388.82
集体企业27.2039.2551.8972.636.9112.0416.4325.31
私营企业6.4715.5036.7579.361.052.259.0721.08
其他0.360.430.570.510.480.480.920.07
总值中:
工业制成品174.87210.45273.57391.5363.5979.97102.93166.63
初级产品19.5519.3220.5424.5020.3118.2522.5231.57

2000年至2003年,集体企业的进口总额约为私营企业进口总额的( )。

A.2.2倍

B.2.1倍

C.1.9倍

D.1.8倍

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