在物理学中，磁场的强弱用磁感应强度（用字母B表示，国际单位是特斯拉，符号是T）来表示，磁感线越密的地方，磁场越强，磁感应强度B越大.

（1）在图20中，甲为某磁极附近磁感线的方向和分布的示意图，由图可知，该磁极为 ▲ 极，若在l处放置一个小磁针，当小磁针静止时，其指向应是图乙中的  ▲   .
（2）磁敏电阻阻值的大小随磁场的强弱变化而变，图丁是某磁敏电阻R的阻值随磁感应强度B变化的图象，据图线可知，磁敏电阻的阻值随磁感应强度B的增大而▲ ．图线没有过坐标原点，说明  ▲  .
（3）王强设计了一个可以测量该磁敏电阻R的电路如图丙所示，（其中磁敏电阻所处的磁场未画出）．将该磁敏电阻R放置在磁场中的位置某处，测出电阻后，利用R—B特性曲线可以读出相应的磁感应强度.
①在图甲磁场中1处，测得的数据如图20表中所示，则该磁敏电阻的测量值为 ▲ Ω. 
②根据该磁敏电阻的R-B特性曲线可知，1处的磁感应强度为   ▲    T.
③在实验过程中，仅将磁敏电阻从1处移至2处，其它条件不变，那么电流表的示数
▲   （填“增大”、“减小”或“不变”）.
④依据上述方法获得的磁感应强度B的测量值与该点实际值存在不小的误差，为尽可能准确反映空间某点磁场的强弱，你认为在选择磁敏电阻时应注意什么问题？

根据句意，用适当的介词或副词完成下列句子

1.When the sun began to go down, he stopped and put 　　  　    a tent (帐篷).

2.We tried to cheer her up 　　  　    telling her funny stories.

3. Could you please come up 　　  　    some ideas for making money?

4. We gave 　　  　    some money to some poor children in Yushu.

5. He called 　　  　    his parents asking for some money.

 

 

你已经是初中生了，想必你一定有你自己的一片“天空”——小房间了。你能用英语描述出你是如何摆设你的东西吗？

要求1.语句通顺达意； 2.至少要写五句； 3.要有on, in, under等表示方位的介词。

 

Jack is a businessman. He has three friends. They are Mary, Ann and David. Jack has a car. He drives to work. Mary works in a hotel. She goes to work on her bicycle. Where does Ann work? She works in a supermarket. She is a clerk. She goes to work by bus. David works in a park, and the park is not far from his home. How does he go to work? He walks to work.
The four friends often have parties on weekends.
表示职业的词：    1            2       
表示工作单位的词：    3            4             5