A:I'm from U.K.
B:She's from the US
C:I'm from Canada
从高为5 m处以某一初速度竖直向下抛出一个小球,在与地面相碰后弹起,上升到高为2 m处被接住,则这一段过程中( )
take your kite tomorrow?
如图是气孔张开和闭合示意图,下列有关的叙述错误的是( )