如图所示,把卡片放在杯口上面,再把光滑的扣子放在卡片上。用手指使劲弹一下卡片,卡片飞了出去,则扣子( )
A:落入杯中
B:和卡片一起飞出去
C:飞出去,落在卡片的前面
D:向后飞出去
Good books are like wise friends, because _____ support you to walk forward and help you understand the world.
下列实数中属于无理数的是( )