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问题 填空题

5个人互相传球，由甲开始发球，并作为第一次传球，经过5次传球后，球仍回到甲手里，共有______种传球方式．

答案

传球方式共有：

4×4×4×3×1+12，

=192+12，

=204（种）．

答：共有204种传球方式．

单项选择题

程控交换机中，向用户终端提供接口电路，完成用户话务的集中和扩散，以及对用户侧的话路进行必要控制的模块是（）

A、用户模块

B、中继模块

C、信号设备

D、数字交换网络
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单项选择题

The common cold is the world’s most widespread illness, which is plagues that flesh receives.
The most widespread mistake of all is that colds are caused by cold. They are not. They are caused by viruses passing on from person to person. You catch a cold by coming into contact, directly or indirectly, with someone who already has one. If cold causes colds, it would be reasonable to expect the Eskimos to suffer from them forever. But they do not. And in isolated Arctic regions explorers have reported being free from colds until coming into contact again with infected people from the outside world by way of packages and mail dropped from airplanes.
During the First World War soldiers who spent long periods in the trenches, cold and wet, showed no increased tendency to catch colds.
In the Second World War prisoners at the notorious Auschwitz concentration camp, naked and starving, were astonished to find that they seldom had colds.
At the Common Cold Research Unit in England, volunteers took part in Experiments in which they gave themselves to the discomforts of being cold and wet for long stretches of time. After taking hot baths, they put on bathing suits, allowed themselves to be with cold water, and then stood about dripping wet in drafty room. Some wore wet socks all day while others exercised in the rain until close to exhaustion. Not one of the volunteers came down with a cold unless a cold virus was actually dropped in his nose.
If, then, cold and wet have nothing to do with catching colds, why are they more frequent in the winter Despite the most pains—taking research, no one has yet found the answer. One explanation offered by scientists is that people tend to stay together indoors more in cold weather than at other times, and this makes it easier for cold viruses to be passed on.
No one has yet found a cure for the cold. There are drugs and pain suppressors such as aspirin, but all they do is to relieve the symptoms.

Which of the following does not agree with the chosen passage

A. The Eskimos do not suffer from colds all the time.
B. Colds are not caused by cold.
C. People suffer from colds just because they like to stay indoors.
D. A person may catch a cold by touching someone who already had one.
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