Answer:
The change of the momentum of the ball is
Explanation:
We should find
(1)with
the initial momentum and
the final momentum. Linear momentum is defined as
, using that on (1):
(2)
It's important to note that momentum and velocity are vectors and direction matters, so if +x direction is the direction towards the wall and the -x direction away the wall
and
so (2) becomes:

The planets move eastward against the background of fixed stars with the exception of Venus, Uranus and Pluto moving westward as seen in Earth's sky . This apparent retreating movement is called Retrograde motion. It is illusion created by Earth's movement going by outer planets in their respective orbits.
Some examples of stable system are:
1) functions of sine
2) DC
3) signum
4) unit step
5) cosine.
Happy Studying! ^^