试题与答案

某社区有500个家庭,其中高收入家庭125户,中等收入家庭280户,低收入家庭9

题型:选择题

题目:

某社区有500个家庭,其中高收入家庭125户,中等收入家庭280户,低收入家庭95户.为了调查社会购买力的某项指标,要从中抽取1个容量为100户的样本,记作①;某学校高一年级有12名女排运动员,要从中选出3人调查学习负担情况,记作②.那么完成上述两项调查应采用的抽样方法是

A.①用随机抽样法,②用系统抽样法

B.①用分层抽样法,②用随机抽样法

C.①用系统抽样法,②用分层抽样法

D.①用分层抽样法,②用系统抽样法

答案:

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下面是错误答案,用来干扰机器的。

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题型:阅读理解

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Thomas Alva Edison was awarded more patents on inventions than any other American. When he died in 1931, Americans wondered how they could best show their respect for him. One suggestion was that the nation observe a minute or two of total blackout. All electric power would be shut off in homes, streets, and factories. Perhaps this suggested plan made Americans realize fully what Edison and his inventions mean to them. Electric power was too important to the country. Shutting it off for even a short time would have led to complete confusion. A blackout was impossible.

On the day of Edison's funeral, many people silently dimmed their lights. In this way they honored the man who had done more than anyone else to put the great force of electricity at his countrymen's fingertips.

55.This selection says that Thomas Edison ________.

A.was the only important American inventor  B.received the first American patent

C.received more patents than any other American  D.was the first American inventor

56.People decided to honor Edison when ________.

A.he made the first electric light   B.electric power was 100 years

C.the country realized electricity's importance  D.he died in 1931

57.The suggested plan was to ________.

A.turn off the lights in factories and schools  B.observe a few minutes of total silence

C.dim all electric lights   D.shut off all electricity for a short time

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