试题与答案

数据3、1、x、-1、-3的平均数是0,则这组数据的方差是  [ ] A.1 B

题型:选择题

题目:

数据3、1、x、-1、-3的平均数是0,则这组数据的方差是   [ ]

A.1

B.2

C.3

D.4

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

阅读理解

     Once upon a time, two brothers who lived on neighboring farms fell into conflict (冲突). It was

the first serious one between them in 40 years of farming peacefully side by side. In the end, they

fell apart.

     One morning, a man with a carpenter's toolbox came for some work.  The elder brother said,

"I just have a job for you. Look at the farm across the creek (河沟). My younger brother lives

there. It was he who used his bulldozer (推土机) to dig the creek last week to spite (刁难) me.

So I want you to build me a fence, an 8foothigh fence, in order not to see his place any more."

The carpenter smiled and said, "I see. I'll try to do a job that satisfies you." Then the elder brother

went downtown.

     At sunset when the farmer returned, the carpenter had just finished his job. The farmer's eyes

opened wide! To his surprise, there was no fence there at all! Instead, there was a bridge stretching

from one side of the creek to the other! A fine piece of work! He saw his younger brother coming

to him with the hands outstretching. The brothers stood at each end of the bridge, and then they

met in the middle, taking each other's hands. They turned to see the carpenter lift his toolbox on

his shoulder. "No, wait! Stay a few days. I've a lot of other work for you," said the elder brother.

"I'd love to stay on,"  the carpenter said, "but I have so many more bridges to build."

1. What was the life like for the two brothers before the conflict?

A. They lived a poor life.

B. They lived in peace.

C. They never spoke to each other.

D. They lived on the same farm.

2. It can be learned that the carpenter was ________.

A. unwilling to obey the farmer

B. fond of building bridges

C. unable to build a fence

D. willing to help others

3. The best title for this passage is ________.

A. A Fine Piece of Work

B. A Carpenter

C. A Conflict Between Two Brothers

D. Two Brothers

4. Which of the following is TRUE according to the passage?

A. The elder brother used his bulldozer to dig a creek.

B. The elder brother helped the carpenter build the bridge.

C. The brothers were both satisfied with the carpenter's work.

D. The carpenter planned to build an 8foothigh fence as asked to.

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A.30 000元和70 000元

B.47 000元和115 000元

C.63 000元和53 000元

D.53 000元和125 000元

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