如图，A是多匝线圈，B是单匝闭合金属环.A中通有变化电流时，B中会产生感应电流，

In Miami, thousands of students have been out of class for some days because of Hurricane Wilma. Educational officials are worried about the long break will affect students’ school performance.

“We think that the sooner we get back to business, the better,” said Rudy Crew, headmaster of Miami-Dade School. 360, 000 students in this area will return to class on Thursday, 10 days after Wilma hit South Florida.

More than half the district’s 327 school buildings were seriously damaged when Wilma struck on October 24, and 270 buildings lost electrical power. About 30 buildings are still out of  power, but lights may be back on Thursday when students return. In Broward County, schools will remain closed through Friday, because more than 100 buildings have been damaged after the storm. With traffic affected by broken stoplights, officials are worried about the safety of children traveling to and from school.

In Miami-Dade County, the nation’s fourth largest school district, officials are considering ways to make up for lost time. They may make the school year longer and reduce days from two-week holiday break in late December, said spokesman John Schuster.

Some parents also worry about the effect of lost school days. “They’re missing important tests and lessons that they are going to need. And how do you catch up with that lost time? It just disappears,” a high school student’s mother said.

“Although things are difficult, students’ performance in hurricane-damaged district may not be seriously affected by the hurricane”, said Florida Education Commissioner John Winn. “It turned out that hurricane-affected districts showed more learning gains than other districts in previous years. They have learned how to fight against disaster in any time. Things will turn better anyway.”

40. When will students return to school in the district?

A. October 24.                B. October 31.      

C. November 3.                     D. November 7.    

41. Which of the following statements is NOT true according to the passage?

A. Many school buildings were seriously damaged.

B. Many school buildings lost electrical power.

C. Some parents also worry about their kids’ studies.

D. Some students got killed when they were at school.

42. According to the passage, we know that _____.

A. maybe students will not have the two-week holiday in late December as usual

B. the school buildings which lost electrical power have all returned to normal

C. some parents don’t think the hurricane affect their children’s performance much

D. John Winn thought that students’ performance would get worse due to the hurricane

43. Which of the following is the best title of the passage?

A. Hurricane Wilma hit South Florida

B. Parents worry about children’ education

C. Hurricane Wilma affected school days

D. Damage by the Hurricane Wilma

写出下列语句的句式特点。

①南冥者，天池也。（___________）

②野马也，尘埃也，生物之以息相吹也。（____________）

③此小大之辩也。（___________）

④去以六月息者也。（____________）

⑤而莫之夭阏者。（___________）

⑥之二虫又何知？（___________）

⑦奚以知其然也？（___________）

⑧而彼且奚适也？（___________）

心主血脉的意义在于（）

A.心是人体主呼吸的重要器官

B.心是人体思维的源泉

C.心是运送血液的重要器官

D.心是人体不可或缺的重要器官

在中点接地的三相四线制低压供电系统中，为了防止触电事故，对电气设备应采取的措施为（）。

A．保护接零(中)线

B．保护接地

C．保护接中线或保护接地

D．无法实现保护作用