已知生产函数为Q=fK，L=10KLK+L，试求劳动的边际产量以及平均产量函数。

如果数a在数轴上所对应的点与原点的距离等于4，那么这个数a=______．

心肌缺氧引起冠状动脉舒张，主要通过下列哪一因素引起（）

A.二氧化碳

B.组胺

C.腺苷

D.前列腺素

E.肾上腺素

震惊中外的中石油吉化公司双苯厂大爆炸，污染了（）

A、松花江

B、长江

D、黄河

D、珠江

Directions: Read the following passage. Answer the questions according to the information given in the passage

and required words limit. Write your answers on your answer sheet.

     If pollution continues to increase at the present rate, formation of aerosols (微粒) in the atmosphere will

cause the start of an ice age in about fifty years' time. This conclusion, reached by Dr S.I. Rassool and Dr S.

H. Schneider, of the united States Goddard space flight center, answers the apparently conflicting questions

of whether an increase in the carbon dioxide content of the atmosphere will cause the earth to warm up or

increasing the aerosol content will cause it to cool down. The Americans have shown conclusively that the

aerosol question is dominant.

     Two conservationists (环境保护主义者) have been the possibility that interfering with the environment

might lead to the planet's becoming unbearably-hot or cold. One of these conservationists has now been laid,

because it seems that even an increase in the amount of carbon dioxide in the atmosphere to eight times its

present value will produce an increase in temperature of only 20℃, which would take place over several

thousand years. But the other problem, now seems larger than ever.

     Aerosols are collections of small liquid or solid particles (微粒) disappeared in air or some other medium.

The particles are all so tiny that each is composed of only a few hundred atoms. Because of this they can float

in the air for a very long time. Perhaps the most commonly experienced aerosol is industrial smog of the kind

that used to be seen in London in the 1950s and is an even greater problem in Los Angeles today. These

collections of aerosols reflect the sun's heat and thereby cause the earth to cool.

     Within fifty years, if no steps are taken to curb the spread of aerosols in the atmosphere, a cooling of the

earth by as much as 3.5℃ seems unavoidable. If that lasts for only a few years it would start another ice age,

and because the growing ice caps at each pole would themselves reflect much of the sun's radiation it would

probably continue to develop even if the aerosol layer were destroyed.

1. According to Rassool and Schneider, what will the global climate be like in 50 years' time? (No more than

    five words.)

    _____________________________________________________________________________________

2. What might be the cause of the ice age? (No more than 5 words.)

    _____________________________________________________________________________________

3. How can the aerosols in the atmosphere cool the earth down? (no more than 5 words.)

    _____________________________________________________________________________________

4. What does the passage mainly tell us? (No more than 6 words.) 

    _____________________________________________________________________________________

违背严谨治学求是性原则（）

A.仅从个人兴趣或追逐个人利益出发选择研究课题是不道德的

B.居里夫人把氯化镭包在自己的前臂上观察镭对人的皮肤的烧伤状况，表现了崇高的道德

C.由个人完成发明创造的时代，已经同爱迪生一去不复返了

D.1969年至1981年的12年间，年轻的心脏病研究者约翰·达西博士共编造假论文100篇以上

E.尸体解剖有利于医学的发展和总结医疗经验