A:50%
B:40%
C:60%
D:30%
—Why did Peter look upset?
—His boss asked him to leave.________,he was fired.
如图所示,小明将篮球向篮框抛出,说明力可以改变物体的____;球离手后,由于____继续向上运动;球在上升到最高点的过程中,动能转化为____能.