问题 问答题 简答题

怎样预防分析结果的误差?

答案

参考答案:

(1)增加实验次数,取多次测量的平均值。

(2)必要时进行重复采样分析。

(3)严格遵守岗位责任制,增加工作责任心,精神集中,细心操作和细心计算。

阅读理解

阅读理解。

     There are some easy things you can do to protect the environment and the earth. Choose ideas from the

list or come up with a few of your own.

      # Plant flowers, grass or trees.

      # Whenever you visit a park or beach, take away what you bring there and keep litter in a bag until you

can put it in a dustbin (垃圾箱).

      # Turn off the lights, TV sets when you leave the room. This saves a lot of electricity.

      # Turn off the tap when you brush your teeth. You can save some water by not letting it run. Also, use

a glass cup instead of a paper cup because this saves paper.

      # Keep the doors and windows closed in winter to keep warm air in.

      # Give your old books and magazines to a library instead of throwing them away.

      # Give your old clothes to poor children you know instead of throwing them away.

      # Use both sides of paper.

      # Stop pouring dirty water into the rivers or lakes nearby.

      # Encourage all your friends to do the same things you do to help protect the earth.

      You don't have to wait until Earth Day to do these things. Make every day Earth Day. If everyone

makes a contribution to protecting the environment, the world will become more and more beautiful.

1. From the above, we know that this is ______.

A. a proposal (倡议书)

B. a poster

C. an ad

2. The writer tells us ______.

A. to pour dirty water into the rivers

B. to throw litter into a dustbin

C. to save water by letting it run while we are brushing our teeth

3. We can ______ to save paper.

A. use a paper cup

B. throw old books away

C. use both sides of paper

4. Which of the following is WRONG according to the writer?

A. Give your old clothes to the poor children.

B. Close the doors in winter.

C. Use a paper cup when you brush your teeth.

5. The main idea of this passage is how to ______.

A. save water and electricity

B. protect the earth

C. make better use of old things

单项选择题