Question

Changing science?

Three Shanghai high school students may have recently overturned （推翻）a scientific theory found in many books.After four months of work they say the well?known Mpemba effect（姆潘巴现象）does not exist.?

Scientists are now checking to see if their discovery is real.The Mpemba effect says that hot water freezes faster than cold water.?

Ye Shasha is a Senior 3 student at Shanghai Xiangming Middle School.She first learned about the Mpemba effect from the book，100 000 Scientific Facts when she was in primary school.“I found it hard to understand but never doubted it.But our experiments show this phenomenon can never happen，”Ye said.?

Last year，an article about the Mpemba effect took first prize in a Shanghai science competition.But Huang Zengxin，a 57－year－old physics teacher in the school，found that the author made some mistakes while reasoning that hot water only freezes faster than cold water under certain conditions.?

Last November，he discussed his ideas with his students，Ye and Senior 2 Yu Shunxi who were very interested in the issue.?

　　They decided to do some serious research into the matter.To support their experiments，the school bought them advanced equipment.?

“I read a lot about the Mpemba effect.But，most explanations，either for or against，are usually based on guesswork（猜测）.We just wanted to let detailed experimental data （数据） do the talking，”said Huang.?

　　Dong Jiawen，a Senior 2 from Shanghai High School，joined the team.She spent all her weekends and all winter holidays working on the project.?

“I have learnt so much from carrying out over 100 experiments，”Dong said.“Most importantly，I've realized that you have to do something yourself in order to find out the truth.Books only serve as a kind of reference（参考）.”?

“The three girls have developed a matter of fact attitude to daily phenomena in the process of examining this effect，”said Huang proudly.?

The Mpemba Effect?

The Mpemba effect says that hot water freezes faster than cold water.The discovery was made by a high school student named Mpemba，in Tanzania（坦桑尼亚），Africa in 1969.He noticed the phenomenon while making ice cream.His teachers did not believe it was possible，and it took several years until university professors finally accepted his discovery.The phenomenon is extremely confusing and surprising even to most scientists. But it has been seen as real and studied in plenty of experiments.?

1.Ye Shasha　　 .?

A.is a Senior 3 student from Shanghai High School?

B.doubted about the Mpemba effect when she was in primary school?

C.is one of the three girls who did the experiment?

D.is a very famous scientist of China?

2.Huang Zengxin　　 .?

A.was given first prize for an article about the Mpemba effect?

B.is a physics teacher at Shanghai Xiangming Middle School?

C.discussed his ideas about this issue with his students this year?

D.is a famous physics scientist in Beijing?

3.The school　　 .?

A.organized the science competition?

B.found three students to do the experiments?

C.bought advanced equipment to help them?

D.held a meeting to discuss this discovery

Answer 1

答案：C;B;C