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问题 选择题

物理研究中常常用到“控制变量法”“等效法”“类比法”等科学方法。在下列研究实例中，运用了控制变量法的是； [ ]

A.研究电流的形成原因时，将电流与水流相比较，从分析水流的形成入手来分析电流的形成

B.研究电流的大小时，根据电流产生的效应大小来判断电流的大小

C.研究多个电阻组成的电路时，求出电路的总电阻，用总电阻产生的效果代替所有电阻产生的总效果

D.研究电流与电压大小关系时，保持电阻大小不变，改变电阻两端的电压值，观察电流如何随电压的变化而变化

答案

答案：D

听力题

根据短文内容和首字母提示，在下文空格处填入适当的词使短文完整。(每空一词)

Almost every child in cities has the chance to go to school,but not all children in the countries are  s_▲_ lucky.

There is a girl called Xiao Wen.She is 8 years old and lives in a small v_▲_ in Guangxi.When she was young,she wanted to go to school.But she could not,because her family was too poor to a_▲_ the school fees(学费) for her,  so her parents had to keep her at home. I _▲_ of studying, Xiao Wen worked in the fields with her parents every day.Then Project Hope heard about Xiao Wen.It helped her to go to school. Her wish of study came t_▲_ ,and now she is studying in a school.

U_▲_ ，there are many thousands of children who can not go to school .You can join in Project Hope and help these children.You know all the work n_▲_ money and Project Hope needs your help.

If you give Project Hope ￥300 each year, it can pay for one child to go to school for a w_▲_ year. With more money, Project Hope can b_▲_ new schools,buy good desks,chairs,blackboards and books.Let’s help the children together and give them a c_▲_ to have a good start in life.
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多项选择题

新经济组织按行业划分，有（）。

A、农产品行业的新经济组织

B、机器制造业的新经济组织

C、第一产业的新经济组织

D、高科技行业的新经济组织

E、第三产业的新经济组织
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