一个带电粒子，沿垂直于磁场的方向射入一匀强磁场，粒子的一段径迹如图所示，径迹上的每一小段可近似看成圆弧．由于带电粒子使沿途的空气电离，粒子的能量逐渐减小（带电量不变）从图中可以确定 (      )

在某次举重比赛中，一名运动员在抓举比赛时，将质量为127.5 kg的杠铃举起历时约0.5 s，再停留3 s后放下杠铃.那么，该运动员在举起杠铃过程中的平均功率约为

舍——____——____   寺——____——____

皮——____——____   乎——____——____

    Going to the zoo

    The students of our School go to the zoo. They see a lot of animals. In the afternoon, they get back to school. The teacher asks them which animal is their favourite. Each student gives an answer. Some animals are very popular. Other animals are not. Here is a chart (图表) the students make at school. It shows the animals the students like best.