下列关于基因突变的叙述中，不正确的是：（） A.突变在自然界中具有普遍性，因此对于果

指南针也叫罗盘针，是中国古代发明的指南仪器。 (76) 。磁石吸铁是因为每块磁石两头都有不同的磁极，一头叫正极，另一头叫负极。人类居住的地球也是一个天然的大磁铁，两端分别是地磁南极和地磁北极。根据同性磁极相排斥、异性磁极相吸引的原理， (77) ，无论站在地球的什么地方，它的正极总是指北，负极总是指南。

中国是最早发明指南针的国家，而且也是最早把指南针用于航海的国家。11世纪末，指南针开始用于航海。 (78) ，晚上看星辰，白天看太阳，阴天下雨就依赖指南针。 (79) ，指南针装置本身也得到了改进，慢慢变成了现在的样子。

指南针的发明和应用，不仅使人们克服了远航时不易分辨方向的困难，而且也推动了世界航海事业的发展和文化交流。南宋时，一些阿拉伯商人和波斯商人学会了指南针的制造方法， (80) 。到12世纪末、13世纪初，阿拉伯和欧洲一些国家才开始用指南针来航海。

A．当时海船上的人辨认方向

B．随着指南针在航海上的应用

C．它是利用磁石指极性制成的

D．拿一根可以自由转动的磁针

E．同时又把这个方法传到了欧洲

（）指南针装置本身也得到了改进，慢慢变成了现在的样子。

The school is so poorly equipped that the students here have no ______ to good resources for learning at all.

A．ambition

B．access

C．entrance

D．qualification

期货公司申请停业后又恢复营业的，应当符合期货公司持续性经营规则。（）

阅读理解。

     Education is not an end, but a means to an end. In other words, we do not educate children only for the

purpose of educating them. Our purpose is to fit them for life.

     In some modern countries it has for some time been fashionable to think that by free education for all-one

can solve all the problems of society and build a perfect nation. But we can already see that free education for

all is not enough; we find in such countries a far larger number of people with university degree; they refuse

to do what they think “low” work; and, in fact, work with hands is thought to be dirty and shameful in such

countries. But we have only to think a moment to understand that the work of a completely uneducated farmer

is far more important than that of a professor; we can live without education, but we die if we have no food.

If no one cleaned our streets and took the rubbish away from our houses, we should get terrible diseases in our

towns.

     In fact, when we say that all of us must be educated to fit us for life, it means that we must be educated in

such a way that, firstly, each of us can do whatever work suited to his brains and ability and, secondly, that

we can realize that all jobs are necessary to society, and that is very bad to be ashamed of one's work. Only

such a type of education can be considered valuable to society.

1. The writer of the passage thinks that _____.[ ]

A. education can settle most of the world's problems

B. free education for all probably leads to a perfect world

C. free education won't help to solve problems

D. all the social problems can't be solved by education

2. The writer wants to prove that _____.

A. our society needs all kinds of jobs

B. our society needs free education for all

C. a farmer is more important than a professor

D. work with hands is the most important

3. The purpose of education is _____. [ ]

A. to choose officials for the country

B. to prepare children mainly for their future work

C. to let everyone receive education fit for him

D. to build a perfect world

液环压缩机在工作中从排出口排出的有（）。

A.水

B.蒸汽

C.工作液体

D.被压缩气体