tailieunhanh - Toefl cbt book part 44

Tham khảo tài liệu 'toefl cbt book part 44', ngoại ngữ, toefl - ielts - toeic phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | CliffsTeslpJelpnljOEcF L CIBfo rmation please visit Tai Lieu Du Hoc at CD B Track 5 Narrator Listen to the following discussion about cloud seeding. Woman The lack of rain in Florida has led to a renewed interest in the technology of cloud seeding. Have you heard of it before Man Yes actually. We used to hear about it back in the 70s and 80s. That s a good point. Why don t they do that Woman Mainly because cloud seeding isn t a proven science. While some scientists believe it works there is no scientific proof that it does. Man So what It s better than doing nothing isn t it Woman It s expensive. The research has been very expensive and the act itself is expensive. They aren t willing to take the effort and expense to do something they aren t sure will work. The authorities in Florida don t believe in it. Man How is cloud seeding supposed to work at least according to those who do believe in it Woman Here s a diagram. The concept was created in 1946 by General Electric. An agent usually silver iodide is deposited into a convective cloud which is the type of white fluffy cauliflower-shaped cloud that generally leads to a storm cloud. The agent provides a nuclei or base on which tiny water droplets can condense and once there is enough condensation the small droplets become larger droplets then ice crystals then snowflakes and ultimately rain. Man Don t they use it for agricultural purposes in the Midwest They think it works. Woman They do but not everybody is convinced. Man It sure seems worth it to me to do whatever it takes to stop wildfires. 34. Narrator What does the woman say has led to a new interest in cloud seeding 35. Narrator Does the man indicate that he has heard of cloud seeding before 36. Narrator Why isn t cloud seeding used to combat dry conditions 37. Narrator What does the man imply should be done 38. Narrator What is the correct order of the process for seeding a cloud 410 For more material and information please visit Tai .