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问题 单项选择题

电源分配系统中，电路跳开关（断路器）端头的颜色分有几种，其区别是（）

A.1种：黑色。没有不同点

B.2种：黑色和绿色。黑色是正常构型，绿色包含有连接到SDAC的辅助线路

C.3种：黑色、绿色、黄色。黑色是正常构型，绿色包含有连接到SDAC的辅助线路，黄色表示处于同一系统的电路上

D.4种：黑色、绿色、黄色、红色。黑色是正常构型，绿色包含有连接到SDAC的辅助线路，黄色表示处于同一系统的电路上，红色表明为重要系统的电路跳开关

答案

参考答案：B

完形填空

Venice(威尼斯) is the “Queen” of the Adriatic sea. Every year   1  from all over the world  2__ Italy to visit the city. Do you know  3  they like to go there for a visit?

Venice is a very beautiful city. It is quite different   4  other cities in the world. There   _5  roads or streets in the city. So there aren’t any cars and buses.There are   6  canals(运河) in the city. There is one big canal and 177 small canals. People move   7  and down the canals   8  to go to work,   9_ or visit their friends.

But Venice is sinking. It is going down and the water is going up. In 2040 Venice

will be   10_ water. The Adriatic Sea will cover the city.

小题1:A. thousand people        B. thousands people    C. thousands of people

小题2: A. travel to                      B. travel from               C. traveled to

小题3: A. where                                B. what                               C. why

小题4:A. from                                   B. with                                C. of

小题5: A. are some                            B. aren’t any                        C. aren’t some

小题6: A. many                                 B. any                                 C. much

小题7: A. on                              B. up                                  C. off

小题8:. A. in buses                      B. in cars                      C. in boats

小题9: A. go to shop                          B. go shopping                     C. go to shopping

小题10:. A. under                               B. with                                C. on
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问答题

在海难打捞中，沉船定位和测量海深都要用到超声测位仪（又叫“声呐”），它的探测系统将所获得的数据送到中央处理器进行运算并显示．如图是测量船利用超声测位仪测定海深的示意图．测量中，探测系统必须探测的物理量是______和______，而中央处理器只须运用______这一简单公式进行运算就能显示出海深．
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