问题 单项选择题

某1FC5356发电机输出空载电压低于400V,若电压特性符合发电机空载特性曲线并且断开AVR连接后电压仍小于360V间,一般可能会损坏的是()。

A.限流电阻R短路

B.限流电阻R开路

C.V1损坏

D.L1匝间短路

答案

参考答案:C

阅读理解

阅读理解。

     Many cities around the world today are heavily polluted.Careless methods of production and lack of

consumer demand for environment (环境) friendly products have contributed to the pollution problem.

One result is that millions of tons of glass, paper, plastic, and metal containers are produced, and these

are difficult to get rid of.

     However, today, more and more consumers are choosing "green" and demanding that the products they

buy should be safe for the environment.Before they buy a product,they ask questions like these: "Will this

shampoo damage the environment?" "Can this metal container be reused or can it only be used once?"

     A recent study showed that two out of five adults now consider the environmental safety of a product

before they buy it. This means that companies must now change the way they make and sell their products

to make sure that they are "green," that is,friendly to the environment.

     Only a few years ago, it was impossible to find green products in supermarkets,but now there are

hundreds.Some supermarket products carry labels (标签) to show that the product is green. Some

companies have made the manufacturing (生产) of clean and safe products their main selling point and

emphasize it in their advertising.

     The concern for a safer and cleaner environment is making companies rethink how they do business.

No longer will the public accept the old attitude of "Buy it, use it,throw it away, and forget it. "The public

pressure is on, and gradually business is cleaning up its act.

1. It becomes clear from the text that the driving force (动力) behind green products is _____.

A. public caring for the environment

B. companies,desire for bigger sales

C. new ways of doing business

D. rapid growth of supermarkets

2. What would be the best title for the text?

A. Business and People

B. Business Goes Green

C. Shopping Habits Are Changing

D. Supermarkets and Green Products

3. The underlined word "it" in the fourth paragraph refers to _____.

A. a selling point

B. the company name

C. a great demand for health foods

D. the manufacturing of green products

单项选择题