下列氧化物中属于两性氧化物的有()A、BaO B、ZnO C、Al2O3 D、Fe3O4

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问题:

下列氧化物中属于两性氧化物的有()

A、BaO

B、ZnO

C、Al2O3

D、Fe3O4

考点:涂装工考试高级涂装工高级涂装工题库
题型:单项选择题
阅读下列短文,根据短文中的信息完成文后表格。(每空一词)
In the past, man did not have to think about the protection of his environment. There were not many people on earth, and natural resources seemed to be unlimited.
Today, things are different. The world has become too crowded. We are using up our natural resources too quickly, and at the same time we are polluting our environment with dangerous chemicals. If we continue like this, human life on earth will not survive.
Everyone realizes today that if too many fish are taken from the sea, there will soon be none left. Yet, with modern fishing methods, more and more fish are caught. We know that if too many trees are cut down, forests will disappear and nothing will grow on the land. Yet, we continue to use bigger and more powerful machines to cut down more and more trees.
We realize that if rivers are polluted with waste products from factories, we will die. However, in most countries waste products are still put into rivers or into the sea, and there are few laws to stop this.
We know, too, that if the population of the world continues to rise at the present rate, in a few years, there will not be enough food.
What can we do to solve these problems?
If we eat more vegetables and less meat, we will easily get more food. Land that is used to grow crops can feed five times more people than land where animals are kept.
The world population will not rise so quickly if people use modern methods of birth control.
Finally, if we educate people to think about the problems, we shall have a better and cleaner living place in the future.
The importance of    小题1:   the environment
Problems
◆ More fish being caught.
◆ More   小题2:   being cut down.
◆ More waste products being    小题3:    into rivers.
◆ More     小题4:   being born.
Causes
◆ The world is becoming too    小题5:   .
◆ Modern methods make the situation  小题6:   .
   小题7:    
We human beings will not survive on the earth.
Solutions
◆ Eat more vegetables and less meat so that more food will be
  小题8:   for everyone.
◆ Use modern methods of    小题9:   control so that the population will not grow too fast.
◆ Educate people so that the    小题10:   will be better and cleaner.
题型:单项选择题

关于物体的运动,不可能发生是(  )

A.速度很大而加速度却很小

B.加速度逐渐减小,而速度逐渐增大

C.加速度方向始终保持不变,而速度的方向发生改变

D.加速度(不为零)保持不变,速度也保持不变

题型:单项选择题
填一填.
6
8
=
()
4
9
18
=
1
()
18
15
=
6
()

16
20
=
()
5
6
15
=
2
()
1000
1000
=
1
()
题型:单项选择题

宾馆作为加油站的柴油客户,一般不采用()的方式结算。

A、现金

B、支票

C、IC卡

D、记账

题型:单项选择题

恶性苗勒管混合瘤(癌肉瘤)几乎总是发生于()

A.育龄期妇女

B.幼女

C.青春期女性

D.绝经后妇女

E.更年期妇女

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