试题与答案

抽样研究中,σ为定值,若逐渐增大样本例数,则样本() A.标准差减小 B.当η趋近无

题型:单项选择题 A1型题

题目:

抽样研究中,σ为定值,若逐渐增大样本例数,则样本()

A.标准差减小

B.当η趋近无穷大时,标准差降至0

C.标准误减小

D.标准误波动范围增大

E.标准误、标准差都不改变

答案:

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参考答案:E解析:本题考查抗凝药的作用特点。肝素以起效迅速,在体内、外均有抗凝作用,可防止急性血栓形成而成为对抗血栓的首选。华法林与肝素相比,优点是口服有效、应用方便、价格便宜且作用持久,其缺点是起...

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题型:阅读理解

I came to live here where I am now between Wounded Knee Greek and Grass Greek. Others came too, and we made these little grey houses of logs that you see, and they are square, It is a bad way to live, for there can be no power in a square.

You have noticed that everything an Indian does is in a circle, and that is because the Power of the World always works in circles, and everything tries to be round. In the old days when we were a strong and happy people, all our power came to us from the respectful circle of the nation, and so long as the circle was unbroken, the people were getting rich. The flowering tree was the living center of the circle, and the circle of the four quarters nursed it. The east gave peace and light, the south gave warmth, the west gave rain, and the north with its cold and strong wind gave strength and continuous power. This knowledge came to us from the outer world with our brief. Everything the Power of the World does is done in a circle. The sky is round, and I have heard that the earth is round like a ball, and so are all the stars. Birds make their nests in circle, for theirs are the same as ours. The sun comes forth and goes down again in a circle. The moon does the same, and both are round. Even the seasons form a great circle in their changing, and always come back again to where they were. The life of a man is a circle from childhood to childhood, and so it is in everything where power moves. Our places were like the nests of birds, and these were always set in a circle, the nation’s circle, a nest of many nests, where the Great Spirit meant for us to nurse our children.

But the Wasichus (Indian word for “white people”) have put us in these square boxes. Our power is gone and we are dying, for the power is not in us any more. You can look at our boys and see how it is with us. Where we were living by the power of the circle in the way we should, boys were men at twelve or thirteen years of age. But now it takes them very much longer to be bull - grown.

小题1: According to the passage, the Indians _______.

A.don’t have modern instruments in their homes

B.refused to move from round places

C.lived in round places, but were forced to live in square houses

D.lived in round places, but then decided to move into square houses小题2:Two things being compared in the passage are _______.

A.the Indians’ past and present living conditions

B.the Indians’ past and modern beliefs

C.the Indians’ old and new power

D.people and nature小题3:In the second paragraph “the four quarters” refers to _______.

A.the four rooms of the Indian’s house

B.the four kinds of natural power

C.the four seasons

D.the four directions小题4:According to the author, once the Indians moved into square houses, _______.

A.they had to move to other houses

B.boys took more time to grow into men

C.they forgot the old way of life

D.everyone was not happy

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