Answer:

Step-by-step explanation:
To determine the muzzle velocity of the gun, we must know how long does it take the ball to strikes the ground

Since the ground is at y=0 and


Solving for t

Now, to determine the muzzle velocity we need to find its acceleration first
(1)
(2)
If we analyze the final velocity is 0. From (2) we have that
(3)
Replacing (3) in (1)



Solving (3)
