Answer:
The acceleration of the ball is 
Explanation:
From the question we are told that
The maximum height the ball reachs is 
The horizontal component of the initial velocity of the ball is
The vertical component of the initial velocity of the ball is 
The vertically motion of the ball can be mathematically represented as

Here the final velocity at the maximum height is zero so 
Making the acceleration
the subject we have

substituting values


The negative sign shows that the direction of the acceleration is in the negative y-axis
Mechanical waves require a medium to travel, but electromagnetic waves do not.
Answer: All r not
Explanation: because u did not list the items
Explanation :
Edwin Hubble used a telescope to discover the movement of galaxies in 1929. He was an American Astronomer.
The telescope invented by him is called a Hubble telescope. It has a 2.4-meter mirror.
He gives the relation between the distance to a galaxy and its recessional velocity. This is known as the Hubble law. The relation is as follows :

where,
is recessional velocity.
is Hubble constant.
is distance.
<em>So, the given statement is True.</em>