下列常用的混合物分离或提纯操作中,需使用冷凝器的是 A.过滤 B.蒸发 C.蒸馏

题型:选择题

问题:

下列常用的混合物分离或提纯操作中,需使用冷凝器的是                                  

A.过滤

B.蒸发

C.蒸馏

D.分液

考点:物质的分离离子的检验粗盐的提纯
题型:选择题

阅读理解。

     Sally was a student. It was going to be her mother's birthday. She wanted to buy her a present that would

be nice and useful but not expensive.

     A week before her mother's birthday, she went shopping after a quick and simple lunch. When she had

been looking for half an hour, she found a shop that was selling cheap umbrellas, and decided to take a black

one since her mother had lost hers the month before.

     She thought, "You could carry that when you are wearing clothes of any color."So she decided to buy a

lovely black umbrella and took to the school with her until her classes had finished.

     On her way back home in the train that evening, she felt hungry because she had such a small lunch that

she went along to the buffet car (便餐车) for another sandwich and a cup of coffee. She had left the black

umbrella above her seat in the compartment (车厢), but when she got back, it had gone! When she had left

the compartment, there had been no other passengers in it, but now there were three.

     Sally began to cry when she saw that the umbrella was no longer there. The other passengers felt very

sorry for her and asked what the matter was.She told them that the black umbrella she had bought for her

mother was gone, and that she had to get out at the next station. After the three other passengers heard it,

they asked her for her mother's address so that they could send the umbrella to her if someone had taken it

by mistake, and brought it back after Sally had got out of the train.

     The next week, Sally heard from her mother. It said, "Thank you very much for your lovely presents,

but why did you send me three black umbrellas?"

1. Which of the following has the same meaning with the sentence "You could carry that when you are

    wearing clothes of any color"?

A. You can carry it when you are wearing any clothes.

B. Any color of your clothes will be all right.

C. The umbrella will be OK for your clothes in any colors.

D. You can take any clothes that you like to wear.

2. Where did she find the umbrella missing?

A. The compartment.

B. Her school.

C. The buffet car.

D. The shop.

3. From the passage, we can infer (推断) that _______.

A. her mother would write to her if she didn't receive the present

B. the three umbrellas were sent by the girl

C. only four peoele had ever been to the compartment

D. nobody brought the umbrella back

4. The best name of the story is _______.

A. A Lucky Girl

B. The Missing Umbrella

C. Mother's present

D. A Happy Mother

5. What does the writer want to tell us?

A. You should take care of your things when you are traveling.

B. Show your love to others, and they will bring you love.

C. Chinldren should often come back to see their parents.

D. It's no use crying when you are in trouble.

题型:选择题

站在开发商的角度上,企业利润可以分为()等四个层次。

A.经营利润

B.建造利润

C.实现利润

D.税后利润

E.可分配利润

题型:选择题

烧伤早期出现的休克多为()

A.神经源性

B.心源性

C.感染性

D.低血容量性

E.失血性

题型:选择题

定量研究以()为方法论基础。

A.反实证主义

B.社会互动论

C.现象学

D.实证主义

E.解释学

题型:选择题

当前,我国经济社会发展进入新阶段,国内外环境更为复杂,挑战增多。()

A、转变经济发展方式和调整经济结构的任务更加紧迫和艰巨

B、城乡之间、地区之间发展不平衡,收入分配不公平和差距扩大

C、社会结构和利益格局深刻调整,部分地区和一些领域社会矛盾有所增加,群体性事件时有发生

D、一些领域腐败现象仍然易发多发,执法不公、行政不作为乱作为等问题比较突出

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