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问题 填空题

(4分)请应用“物质性质决定用途”的规律，完成下表：

 物质化学式性   质用   途
例子CO2在一定温度下能形成固体制作干冰，用于人工降雨
(1) 在空气中可燃烧可作为火箭发射燃料
(2)   

答案

(4分) H2   O2  在空气中可支持燃烧  可供给呼吸 （合理答案即可）

题目分析：可以根据物质的性质和用途方面进行分析、判断，从而得出正确的结论。

（1）    氢气能在空气中燃烧，可以作为气体燃料；

（2）    可以填O2，氧气的性质可填在空气中可支持燃烧、可供给呼吸，用途可填用于炼钢、急救病人等（合理答案即可）。

点评：解答本题要充分理解各种物质的性质，只有理解了物质的性质才能确定物质的用途。

单项选择题

Many small cultural groups live in places far away from modern cities. Some of these tribes have never had any communication outside of their small geographical areas. When they do contact the outside world, their lives usually change. Learning how to change without losing the best of their own cultures is a problem for them. How can primitive cultures learn to live in a technological world How can they do this without becoming lost
One native tribe in New Guinea has a difficult situation. The people of the tribe are being pulled in two ways. First of all, copper, a bright orange-colored metal, has been discovered under the land where they have lived for centuries. Developers want to take the copper out of the ground, to mine it. The tribe needs the money that a copper mine would bring. The problem is that the copper is directly under the most important buildings of their society. These buildings are a necessary part of their religion. How can the copper be mined without changing the group’s religion
The answer to this question has not yet been found. However, a group of people is trying to help the tribe to learn to communicate with the rest of the world. Cultural Survival, Inc. is the name of the group. The people are anthropologists, scientists who study cultures. They want to help small, separate societies live successfully within the larger society. Cultural Survival, Inc. wants to help these groups keep the idea of who they are. It wants to teach them how to live in the modern world.
There is another organization like this in London. It is called Survival International. One in Copenhagen is called the International Workshop for Indigenous Affairs. These two groups have joined with Cultural Survival, Inc., to help people become used to modern culture.
These organizations work with another kind of problem, too. Sometimes a central government does not consider the needs of local people. Often the rich people of a country will get more from a new project than the working people. The poorer people sometimes suffer even more because of these projects. One thoughtless government leader moved the people out of a very large area. He wanted to set up a special vegetable business. He wanted something to sell to earn money from other countries. About 50,000 people were forced off their native land. These people suffered a great loss because they had to leave their homes. Cultural Survival, Inc. helped them.
Cultural Survival, Inc. and its sister organizations also give advice about tourism. The tourism business can cause problems. Many small societies need to earn money, but a large group of visitors can hurt their culture. The Sherpas of Nepal are a good example. The beauty of the Himalayan Mountains brings many mountain climbers from all over the world. However, the tourists leave tin cans and other garbage. What the tourists leave behind in this beautiful area is making a garbage dump. The mountain climbers are also cutting down trees for their fires. This area has few trees, and the Sherpas need the wood for their uses. The Sherpas, it is clear, could use the help of Cultural Survival, Incorporated.

Para. 2 shows that

A．the economy of the native tribe develops rapidly.

B．the tribe is good at mining copper.

C．there is a problem that holds the tribe back from developing.

D．copper is a necessary part of the tribe’s building.
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问答题 简答题

试述低蛋白、低盐饮食的饮食原则和适用范围？
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