《城镇燃气设计规范》GB50028将燃气管道按压力分为（）。 A.3级 B.4级 C

BB减少表示（）。

A.碱中毒

B.CO₂潴留

C.酸中毒

D.代谢性碱中毒

E.代谢性酸中毒

阅读理解。

     People all over the world today are beginning to hear and learn more and more about the

problem of pollution. Pollution is caused either by man's release of completely new and often

artificial substances into the environment, or by releasing greatly increased amounts of a natural

substance , such as oil tankers into the sea.

     The whole industrial process which makes many of the goods and machines we need and

use in our daily lives, is bound to create a number of waste products which upset the

environmental balance, or the ecological balance as it is also known. Many of these waste

products can be prevented or disposed of sensibly, but clearly while more and more new

and complex goods are produce there will be new, dangerous wastes to be disposed of, for

example, the waste products from nuclear power stations. Many people, therefore, see

pollution as only part of a larger and more complex problem, that is, the whole process of

industrial production and consumption of goods. Others again see the problem mainly in

connection with agriculture, where new methods are helping farmers grow more and more

on their land to feed our ever-increasing populations. However, the land itself is gradually

becoming worn out as it is being used in some cases, too heavily, and artificial fertilizer cannot

restore the balance.

     Whatever its underlying reasons, there is no doubt that much of the pollution caused could

be controlled if only companies, individuals and governments would make more efforts. In the

home there is an obvious need to control litter and waste. Food comes wrapped up three or

four times in packages that all have to be disposed of; drinks are increasingly sold in bottles

or tins which cannot be reused. This not only causes a litter problem, but also is a great waste

of resources, in term of glass, metals and paper. Advertising has helped this process by

persuading many of us not only to buy things we neither want nor need, but also to throw away

much of what we do buy. Pollution and waste combine to be a problem everyone can help to

solve by cutting out unnecessary buying ,excess consumption and careless disposal of the

products we use in our daily lives.

1. The underlined phrase "disposed of "in the second paragraph means_______.

A. dealt with

B. exposed

C. disapproved of

D. collected

2. In the writer's view ,the more new goods, _______.

A. the less pollution

B. the harder pollution can be prevented

C. the more pollution there will be

D. the more easily pollution can be controlled

3. What can we learn from the last paragraph?

A. We can do much to reduce pollution.

B. The government is trying hard to stop pollution.

C. Individuals know how to get rid of the habit of littering everywhere.

D. We can't stop buying unnecessary things.

4. People can help solve the problem of pollution by _______.

A. urging their governments to control litter and waste

B. making anti-pollution advertisements

C. cutting down the use of oil and other oil products

D. reducing unnecessary buying, over-consumption and careless disposal of wastes

培养基的用途不包括（）。

A.细菌的分离、纯化、培养

B.细菌的传代

C.细菌菌种的保存

D.研究细菌的生化特性

E.研究细菌的致病性

卷烟需求具有季节性变化特性，需求随着时间的变化归因于（）。

A.卷烟投放量变动

B.需求模式的季节性变化

C.心理因素

D.A和B

现金流量图中现金流量的三大要素是( )。

A．投入现金的额度、时间和回收点
B．现金流量的大小、方向和时间点
C．现金流入的大小、方向和时间点
D．现金流出的大小、方向和时间点