不锈钢通常不与酸、碱、盐反应，是下列哪种元素加入的结果( ) A．Ni B．C

将洁净的金属片Fe、Zn、A、B分别与Cu用导线连接浸在合适的电解质溶液里．实验并记录电压指针的移动方向和电压表的读数如下表所示：

金属	电子流动方向	电压/V
Fe	Fe→Cu	+0.78
Zn	Zn→Cu	+1.10
A	Cu→A	-0.15
B	B→Cu	+0.3

根据实验记录，完成以下填空：

（1）构成两电极的金属活动性相差越大，电压表的读数越______．（填“大”、“小”）．

（2）Zn、A、B三种金属活动性由强到弱的顺序是______．

（3）Cu与A组成的原电池，______为负极，此电极反应式为______．

（4）A、B形成合金，露置在潮湿空气中，______先被腐蚀．

（5）铝热反应中的铝热剂的成分是______，工业上常用的铝的冶炼的化学方程式为______．

在百花齐放的唐代文学中，最为光彩夺目的成就是 [ ]

A．散文

B．传奇

C．词赋

D．诗歌

阅读理解。

     The world itself is becoming much smaller by using modern traffic and modern communication means.

Life today is much easier than it was hundreds of years ago, but it has brought new problems. One of the

biggest problems is pollution. To pollute means to make things dirty. Pollution comes in many ways. We

see it, smell it, drink it and even hear it.

     Man has been polluting the earth. The more people, the more pollution. Many years ago, the problem

was not so serious because there were not so many people. When the land was used up or the river was

dirty in one place, man moved to another place. But this is no longer true.

     Man is now slowly polluting the whole world.

     Air pollution is still the most serious. It's bad for all living things in the world, but it is not the only one

kind of pollution. Water pollution kills our fish and pollutes our drinking water. Noise pollution makes us

angry more easily.

     Many countries are making rules to fight pollution. They stop people from burning coal in houses and

factories in the city, and from putting dirty smoke into the air. Pollution by SO₂ is now the most dangerous

kind of air pollution. It is caused by heavy traffic. We are sure that if there are fewer people driving, there

will be less air pollution.

     The earth is our home. We must take care of it. That means keeping the land, water and air clean. And

we must take care of the rise in pollution at the same time.

1. _____, our world is becoming much smaller.

A. Because of the rise in pollution

B. Thanks to science development

C. Because the earth is being polluted day and night

D. Because the earth is blown away by the wind every year

2. Hundreds of years ago, life was _____ it is today.

A. much easier than

B. as easy as

C. much harder than

D. as hard as

3. Pollution comes in many ways. We can even hear it. Here "it" means _____.

A. rubbish (垃圾)

B. noise pollution

C. air pollution

D. water pollution

4. Air pollution is the most serious kind of pollution because _____.

A. it makes much noise

B. it makes us angry more easily

C. it makes our rivers and lakes dirty

D. it's bad for all living things in the world

5. Which of the following is NOT true?

A. Many countries are making rules to fight pollution.

B. The pollution of the earth grows as fast as the world population does.

C. The problem of pollution is not so serious because there are not so many people living on the earth.

D. If people could go to work by bus or bike instead of car or motorbike, it would be helpful in fighting

    against the problem of SO₂.

停电拉闸操作必须按照（）、（）、（）的顺序依次操作。送电操作按与上述（）的顺序进行。

简述YB55型小盒透明纸包装机缺小包拉线或小包透明纸接头检测故障的显示条件、产生的原因及排障措施。