做匀速圆周运动的物体[ ] A．一定受平衡力的作用 B．它受到的力可能平衡，也可

阅读理解。

       Mobile phone has become a problem for middle schools. Some middle schools in Australia

have banned (禁止) students from carrying mobile phones during school hours.

       Mobile phone use among children has become a problem for the schools this year. Several

children have got mobile phones as Christmas presents, and more students want them.

       Mary Bluett, an official (官员) said mobile phone use is a distraction (分心) to students during

school hours and it also gives teachers so much trouble in their classrooms. Teachers were also

saying that sometimes students might use phone messages to cheat (作弊) during exams.

       The official said some schools had tried to ban mobile phones. Some parents felt unhappy

because they couldn't get in touch with their children.

       Many teachers said students should not have mobile phones at school, but if there was a good

reason, they could leave their phones at school office. They also said there were many reasons why

the students should not have mobile phones at school: they were easy to lose and were a distraction

from studies.

       Many people say that they understand why parents would like their children to have phones, but

they think schools should let the students know when they can use their mobile phones.

1. Have some middle schools in Australia banned students from carrying mobile phones at school?

    ______________________________________

2. Probably from whom did some children get mobile phones?

    ______________________________________ 

3. What did some students use phone messages to do? 

    ______________________________________

4. Why did some parents feel unhappy about banning mobile phones at school? 

    ______________________________________

5. Can students use mobile phones for some special reasons?

     ______________________________________

骨肿瘤的好发部位在（）。

A.扁骨

B.脊椎骨

C.长管状骨骨干

D.长管状骨干骺端

E.短管状骨干骺端

《安全评价机构管理规定》生效实施的时间是（）

A.2004年1月1日

B.2005年1月1日

C.2005年6月1日

D.2005年3月1日

按我国温度带和干湿区的划分，龙岩市属于[ ]

A、热带、半湿润地区

B、热带、湿润地区

C、亚热带、半湿润地区

D、亚热带、湿润地区

音频控制面板上复位按钮的作用是什么（）？

A.重新启动系统的工作。

B.取消先前的选择。

C.取消所有的亮灯呼叫。