Questions 16 to 19 are based on the talk in class about United States history.
16. What is the main topic of the talk?
17. According to the professor, what was the major change in agriculture during the 19th century?
18. According to the professor, what was one result of the increased use of machinery on farms in the United States?
19. According to the professor, why was world market important for the United States agriculture?
Passage 6
The energy which the sun radiates goes in every direction. However, only a minute part of it falls on the earth. Even so, it represents the power of about five million horsepower per square mile per day. The sun gives us as much energy every minute as mankind uses in a year. At present, we use this energy indirectly, and it is our only final source of power. Coal represents the chemical action of the sun on green plants thousands of years ago. Water power results from the suns creation vapor and the resulting rain. Even windmills operate because of air currents set in motion by the uneven heating effects of the sun in different places, Already, a scientist has worked out an engine, surprisingly efficient. This engine uses a series of mirrors which concentrate the suns energy on a tube of water to create seam.
Questions 20 to 22 are based on the passage youve just heard.
【6月英语六级考试听力成功指南(第十六期)】相关文章:
最新
2017-01-16
2016-10-21
2016-10-08
2016-10-08
2016-10-08
2016-10-08