题目

As you grow older, you’ll be faced with some challenging decisions—like whether to cut class or try cigarettes. Making decisions on your own is hard enough, but when other people get involved and try to pressure you one way or another it can be even harder. People who are your age, like your classmates, are called peers. When they try to influence how you act, to get you to do something, it’s called peer pressure. Peers can have a positive influence on each other. Maybe another student in your science class taught you an easy way to remember the planets in the solar system. Maybe 如图，物块A和B叠放在一起，A和B接触面粗糙，且质量mA＞mB．让它们一起向右在光滑水平桌面上做匀速直线运动，离开桌面后又一起做平抛运动，不计空气阻力，设运动过程中A、B不分离、不翻转，重力加速度为g，则在它们的运动过程中（　　） A、在水平桌面上运动时，A、B之间既有弹力也有摩擦力B、在做平抛运动时，A、B之间既有弹力也有摩擦力C、在做平抛运动时，A、B之间既无弹力也无摩擦力D、在做平抛运动时，A对B的压力大于0而小于mAg