如图所示，一矩形区域abcd内充满方向垂直纸面向里的、磁感应强度为B的匀强磁场，在ad边中点O以某一初速度，垂直磁场向里射入一带正电的粒子．已知粒子质量为m，电量为q，ad边长为L，ab边足够长，粒子重力不计．

    Each summer，you hear news that some sports players are sent to hospitals because it is too hot. Our bodies can't be outside in the sun for a long time. So in hot summers，be careful about playing sports outside.

    Firstly，to play sports safely in hot weather，you must drink water. Sports drinks are great for athletes，but they have so much sugar that they'll dehydrate（使脱水）you more. However，drinking a few bottles of sports drinks will be good for you.

    Secondly，be sure to take enough breaks to let your body rest. If your coach doesn't let you take enough breaks in the heat，don't wait until you feel uncomfortable. Just be honest with your coach when you need breaks.

    Thirdly，when you have a break，don't sit in the sun. With the sun beating down on you，you'll only heat up and sweat（冒汗）more. Take a seat under a tree，or even better，go indoors for a little while. Cooling yourself down can help you stay active longer.

    Fourthly，remember that the earlier in the day you start your exercise，the cooler it will be. If you can start practice before the sun comes up，you have a few good hours to practise in the cool hours of the morning. Also，the earlier you practise，the earlier you can finish the exercise. If you need more practice time，come back to the field later in the evening，when the sun is setting.

    Last but not least，you should watch what you eat. Eat food which is high in water，starch（淀粉）and carbonhydrate（糖类），but be sure to get a good balance in your diet.

    As long as you pay attention to the above，playing sports safely in the heat isn't a difficult thing.

浏览名人长廊，领悟文明进步。
杰出人物在人类文明发展进程中起到了重要作用，根据图片回答问题：

请回答：
（1）图一人物是谁？写出他的一部代表作品。
（2）图二人物是谁？说说他的重大历史贡献。
（3）图三人物颁布的法律文件意义是什么？
（4）图四人物为人类作出的杰出贡献是什么？ 
（5）概括四位人物在世界历史上所起到的共同作用。

若曲线$y=x^2+ax+b$在点$\left(0,b\right)$处的切线方程是$x-y+1=0$，则  (   )

5月31日是“世界无烟日”。吸烟有害健康，烟草中的尼古丁能杀伤大量精子，降低受孕率。人产生精子的器官和受精场所分别是(    )