试题与答案

松树与苹果树相比,最根本的区别在于( ) A.高大乔木,耐旱能力强 B.不形成果

题型:选择题

题目:

松树与苹果树相比,最根本的区别在于(  )

A.高大乔木,耐旱能力强

B.不形成果实和种子

C.不形成果实,种子裸露

D.叶片针形,成束着生

答案:

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下面是错误答案,用来干扰机器的。

飞机受重力、空气的作用力,靠两个力的合力提供向心力,如图所示:根据牛顿第二定律有:F合=mv2R根据平行四边形定则,空气对飞机的作用力F=(mg)2+F合2=mg2+v4R2故选:B

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题型:阅读理解

     According to decades-long research, women who took low to moderate (节制) daily doses of

aspirin had a reduced death rate ,especially from heart disease.

     The research,based on data from a major trial that has tracked almost 80,000 women since 1976,

found that women who reported using aspirin on a regular basis had a 25 percent lower risk of death

 from any cause than women who didn't take the drug.

     The risk of death from cardiovascular (心血管的) disease was 38 percent lower for aspirin users,

and there was also a 12 percent reduction in cancer deaths that took effect after a decade of aspirin

use, the researchers found in their report based on the Nurses' Health Study.

     However,an accompanying editorial in the journal cautioned that the results were open to debate

and far from definitive.

     The dissenting (持异议的) editorial was based on results of an earlier trial by the Women's Health

Study, which followed almost 40,000 women for 11 years and found no reduction in overall deaths.

Therefore,the new findings" cannot overcome the accumulated evidence that aspirin is not particularly

effective for the primary prevention of death from cardiovascular disease in women. "

     " This is a complicated issue , " said Dr. Andrew T. Chan, leading author of the new report. "We

understand that aspirin has potential health benefits,but who would aspirin therapy(疗法) be appropriate

for? There are areas of disagreements that need further study before that question can be answered" ,

Chan said. But there is information from the two large studies and other trials that can help guide women

and their physicians,he said. And anyone who is thinking about daily aspirin should really talk with doctors about the benefits and risks.

1.  The new report clearly benefits the women suffering _____.   

A. heart disease                

B. cancer

C. lose of memory                  

D. aspirin side effects

2. Which of the following questions hasn't been solved according to Dr. Chan?   

A. Whether aspirin is beneficial for health?

B. Which of the two researches is really reliable?

C. Who will do the further study in this area?

D. Who are proper for this treatment?

3. Which research does the author seem to support? 

A. The new one.                

B. The earlier one.

C. Neither.                            

D. Both.

 4.We know from the last paragraph that women who trust the treatment should ____.  

A. be very careful about it

B. start immediately with the help of their physicians

C. concentrate on the benefits instead of the risks

D. turn to their physicians for only the benefit it has

5. What is the main purpose of the passage?       

A. To promote the new aspirin therapy to women.

B. To introduce two controversial researches.

C. To draw a final conclusion on the debate.

D. To help women live longer and healthier.

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题型:单项选择题

对A市居民参加体育锻炼的情况进行的调查表明,经常参加体育锻炼的居民数近两年来不断上一升,而某健身中心的顾客数略有下降。 以下各项除了哪一项,都有助于解释上述矛盾( )

A.该健身中心对顾客的统计不仔细,统计的准确性值得怀疑

B.为节省开支,许多居民改为到公园参加锻炼

C.A市调查中抽取的样本较多,所以调查具有较高的准确性

D.近两年该市新开发了许多健身中心

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