运用知识解决问题：

（1）如图是水位自动报警装置。当水位上升时，浮子a上升，并推动b上升。当水位达到一定高度时，电磁铁电路接通，电磁铁____________，吸引衔铁，电灯电路__________，电灯发光发出警报，警告水位过高。

（2）请你根据实物电路，在方框中画出电路图。

（3）将电阻R₁和R₂＝12Ω的电阻并联接在电源两极上，测得总电流为0.6A，通过R₁的电流为0.4A。则：①电源电压U＝_________V；②R₁＝__________

One day I told Mr Wang,our math teacher,was ill.                                                                             61.________

I was worried about him and went to see him after the school.                               62.________

When I enter his room,he struggled up to welcome                                              63.________

me.I let him lay down again.Mr Wang looked pale.                                               64.________

I asked about his trouble.He said he was having                                                    65.________

a bad cold.Then he had a bad cough.After take some                                             66.________

medicine he was getting better.He asked me that we                                              67.________

liked the teacher who took place.When he heard                                                   68.________

everything was all right,I could see he was pleasing.                                             69.________

Finally I asked him don’t to worry about the work                                                70.________

and have a good rest.