Frame rate

The previous example represents a naive approach
to animating a bouncing ball:
it alternates the position of the ball
between only two frames,
switching frames once every second.
One way to improve this animation is to use more frames,
which smoothes out the animation
and provides a more convincing illusion of movement.
Consider what changes you need to make to the example
so that, instead of having just two positions,
the ball has five:

frame #

position

movement direction

top margin: 0

top margin: 25

down

top margin: 50

down

top margin: 75

down

top margin: 100

down

top margin: 75

up

top margin: 50

up