未经环保部门批准，不得擅自进口、转让放射性同位素。

等腰三角形的底和腰是方程x²-7x+10=0的两根，则这个三角形的周长是______．

小明同学利用电压表和电流表测量小灯泡的电阻值（已知小灯泡的额定电压为2.5V），实验电路图如图1所示．

图1                                                                  图2

（1）按图1所示的电路图，将图2中的电压表正确连入电路（用笔画线代替导线）

（2）开关闭合前，滑片P应移到_________（填“a“或“b”）端；实验中，当滑片P移到某一位置时，电流表A和电压表V示数如图所示，则此时小灯泡的阻值为_________Ω．

（3）小明在实验时，小灯泡突然熄灭，检查发现A的示数为零，V的示数接近电源电压，请你帮小明分析电路的故障可能是：_________．

（4）若小明同学想用已连好的电路测量小灯泡的额定电功率，请你帮他把主要的实验步骤补充完整：

①移动滑动变阻器的滑片P，使电压表的示数为_________V时，读出电流表的示数；

②用原理_________．

中国近代史开始的时间是1839年。                                            

错误：                      改为：                                    

An unhealthy obsession (着迷)with celebrity(名人) culture is damaging the study success of British students, a survey of teachers found last Friday, with celebrity couple the Beckhams their favorite. Many students are dropping their study to seek the chance of fame instead, the Association of Teachers and Lecturers (ATL) survey found. .Almost two-thirds of teachers said sports stars were the type of celebrity most pupils wanted to copy while more than half of students wanted to be pop stars.

The celebrities students wanted to be most like, the survey said, were Los Angeles-based David and Victoria Beckham, Britain's most famous couple. Soccer player "Beckhams" topped the poll(民意测验), with more than half the teachers saying their students modeled themselves on him. In second place, with almost a third of the poll's vote, was his 33 year-old wife and pop star "Posh."

A majority of teachers said it was television "stars" and a media fixation with celebrities, celebrity culture that negatively impacted the their pupils. Almost half of the 300 teachers polled said pupils tried to look like or behave like celebrities they most admired. What they feared is that girls particularly dressed in "unsuitable.”

"We are not surprised about infiltration(渗透) of celebrity culture in schools" the teacher Mary Boust  said in a statement. "Celebrities can have a positive effect on students. They can raise students' desires and ambitions for the future.

"However, celebrity culture can cause the wrong opinion that celebrity status(地位) is the greatest achievement and the belief that other career choices are not valuable."

5. The survey showed that________

A.  the British students studied hard.

B.  many students dreaming of being famous stars.

C.  Beckhams was a famous football player.

D.  the teacher thought it unnecessary to study hard.

6. The underlined word ”modeled” refers to ______

A.  was fond of    B.  hated     C.  copied    D.  wished

7. Which of the following is NOT right?_________

A.  The survey was carried by the teachers.

B.  Beckham was the most popular with the students.

C.  Celebrities sometimes have a good effect on the students.

D.  The couple Beckhams now still live in England.

8. Which is the best title of the passage?________

A.  British Students Wants to Be Famous

B.  Celebrity Obsession Harming British Students

C.  Teachers Worried about Their Students

D.  The Students’ Opinions Are changing