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倾角为 的光滑绝缘斜面如图所示，在相隔为d的平行虚线MN和PQ与斜面底边平行，其间有大小为B的匀强磁场，方向垂直斜面向下。一质量为m、电阻为R、用相同的金属线做成的边长为L的正方形单匝线框，在斜面上某位置由静止释放，且释放时cd边与斜面底边平行。当cd边刚进入磁场时，线框的加速度大小为a，方向沿斜面向上；线框ab边刚要离开磁场和cd边刚进入磁场时，ab边两端的电压相同。已知磁场的宽度d大于线框的边长L，不计空气阻力，重力加速度People often hear bad news on TV, the “Touching China” award on Tuesday sends a different message. The award honors(给...以荣誉) ten of China’s role models(道德模范) in 2012. The award winners are carefully selected(推选) by people. The “Touching China” award has been held every year since 2003.Luo Yang is one of the ten role models. He is the late Commander in chief(前总指挥官) of the program for developing the J-15 fighter(歼-15战斗机). He died from overwork. And Lin Junde, a scientist who dedicated his whole life to China’s nuclear course(核事业). There are also ordinary citizens(公民) who have made a difference, like Zhang Lili.Zhang Lili, 29, a Chinese language teacher at No. 19 Middle School in the city of Jiamusi, Heilongjiang Province. On the evening of May 8, Zhang was crossing the road outside the school gate with several students. A school bus came rushing towards them. Zhang pushed two students out of the way. They were saved, but Zhang was hit. She was sent to the local hospital but lost both her legs. When facing the choice between life and death — for her students and for herself, Zhang chose to protect her students. Many people were deeply moved by her story. Now people thinks she is the Most Beautiful Teacher in China.小题1: The “Touching China” award is held _________.A．in MayB．every four yearsC．once a yearD．in 2003小题2:What does the underlined word dedicated mean in Chinese?A．赠予B．奉献C．提供D．回报小题3:What happened when Zhang was crossing the road?A．The school bus rushed to them.B．Two students fell over at the school gate.C．Zhang found a bus stop on the road.D．Several students were ill.小题4: Which of the following is TRUE according to the passage?A．Every ordinary citizen can have the chance to win the “Touching China” award.B．The “Touching China” award honors ten China’s scientists as role models of 2012.C．The “Touching China” award tells us bad news like other TV programs.D．Zhang Lili is a really beautiful and brave teacher.小题5:What’s the best title of the passage?A．Two great scientists.B．The “Touching China” award of 2012.C．The Most Beautiful Teacher.D．A moving story of Zhang Lili.