成品啤酒瓶颈空气量愈低，愈有利于非生物稳定性和风味稳定性，瓶颈空气一般要求小于（）m

阅读短文，根据短文内容，从从A、B、C、D四个选项中，选出最佳答案．

Australia is the largest island in the world. It is a little smaller than China. It is in the south of the earth. Australia is big, but its population is small. The population of Australia is nearly as large as that of Shanghai.

Enough laws (法律) have been made to fight against pollution. The cities in Australia have got little air or water pollution. The sky is blue and the water is clean. You can clearly see fish swimming in the rivers. Plants grow very well.

Last month we visited Perth,  the biggest city in Western Australia, and went to a wild flowers' exhibi­tion (展览). There we saw a large number of wild flow­ers we had never seen before. We had a wonderful time. Perth is famous for its beautiful wild flowers. In spring every year Perth has the wild flowers' exhibi­tion. After visiting Perth, we spent a day in the coun­tryside. We sat down and had a rest near a path at the foot of a hill. It was quiet and we enjoyed ourselves. Suddenly we heard bells ringing at the top of the hill. What we saw made us pick up all our things and run back to the car as quickly as we could. There were about three hundred sheep coming towards us down the path.

Australia is famous for its sheep and kangaroos. After a short drive from any town,  you will find your­self in the middle of white sheep. Sheep, sheep, every­where are sheep.

小题1:Australia is        .

A．the largest country in the world

B． larger than China

C．as large as Shanghai

D．not so large as China小题2:Enough laws have been made to        .

A．increase the population

B．grow more plants

C．fight against pollution

D．show wild flowers小题3:Perth is        .

A． the capital of Australia

B． in the west of Australia

C． in the east of Australia

D． the biggest city in Australia小题4:In Perth you may visit a wild flowers' exhi­bition in        .

A．October

B．January

C．May

D．July小题5:Which of the following sentences is TRUE?

A．All the big cities in Australia are serious­ly polluted.

B．Australia is famous for its sheep, kanga­roos and large population.

C．We ran back to the car because we were in the middle of the white sheep.

D．If you go to the countryside in Australia, you will see a large number of white sheep.

I first met Mr. Smith in America. He ______ at Stanford University then.

A．studied

B．has studied

C．is studying

D．was studying

对动脉粥样硬化有保护作用的脂蛋白是（）

A.LDL

B.HDL

C.VLDL

D.CM

E.IDL

造成术中病人低体温的热散失形式不包括（）。

A.辐射

B.传导

C.蒸发

D.冷却

E.对流

简述安全的定义及目的。