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问题 单项选择题

已知某省山区，丘陵，湖区婴幼儿体格发育有较大的差异，现需制订该省婴幼儿体格发育有关指标的正常值范围，调查设计最好采取（）。

A.单纯随机抽样

B.分层抽样

C.整群抽样

D.机械抽样

E.系统抽样

答案

参考答案：B

阅读理解

Answer the questions according to the passage you read.

A great French writer said that we should help everyone as much as we can, because we often need help ourselves. Sometimes the small can help the great. And he told the following story.

An ant was drinking by a small river and fell in. She tried her best to reach the bank(岸), but she couldn’t move at all. The poor ant got too tried but was still doing her best. Then a big bird saw her. The bird threw a piece of wood into the water. With it the ant reached the bank again. While she was resting and drying herself on the grass, she heard a man coming up. The man was walking with a gun(枪) in his hand. As soon as he saw the bird, he wanted to kill her. But the ant bit(咬) him on one of his feet and at the moment the bird flew away at once.

The ant saved the bird’s life.

小题1: According to the French writer, we often need help from others, so what should we do?

                                                     

小题2:What does the sentence “we often need help ourselves”?

                                                      

小题3:Why did the ant couldn’t reach the bank when it fell into the river?

                                                      

小题4:Though the poor ant was too tried, what did she do？

                                                      

小题5:请将画线句子翻译成汉语。

                                                       
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多项选择题

组分A、B的气相色谱分析图谱中，两者未能完全分开，为提高分离度，可采取（）。

A.升高柱温

B.降低载气流速

C.更换色谱柱

D.降低柱温

E.提高载气流速
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