如图所示，木板A、B紧靠在一起，放在光滑水平面上，m_A=5kg，m_B=4kg，A、B上表面粗糙．另有一个质量为1kg的物块C以初速度v₀从A的左端向右滑动，最后C物块在木板B上与木板B一起以1.5m/s的速度运动，木板A最终的速度大小为v_A=0.5m/s．已知C与A、B间动摩擦因数均为μ=0.2，求：

如图甲所示是苏州某路口安装的监控摄像头，它可以拍下违章行驶或发生交通事故时的现场照片，摄像头的镜头相当于一个____ 透镜，它的工作原理与____ （选填“照相机”、“投影仪”或“放大镜”）相似．如图乙和丙是一辆汽车经过路口时与一辆自行车相撞后被先后拍下的两张照片，由图可以看出汽车是逐渐____ （选填“靠近”或“远离”）摄像头．

根据3×8=4×6，你能组成多____个比例?

    Do you want to be healthy and thin? All of us will say: of course! But how to be healthy and thin? If you want to lose weight and keep healthy, the first way is to be on a diet. Eating too much is bad for your health and you will easily turn fat! The best way is to eat a little sugar, but more vegetables! The other way is to do more exercise! Sport is good for your health. You should keep running or walking for about twenty minutes every day. This is the most straightforward method. If you keep doing this for a long time, you will be more healthy.

(词汇提示：1) lose weight 减肥  2） be on a diet 按规定进食；节食  3）a little 少量的 
4）method方法  5）the most straightforward method最直接的方法)