Answer:
20.47 m/s
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration
g = Acceleration due to gravity = 9.81 m/s² = a

Total height of the fall is 29.3577 m
Height the ball reached above the building is 

Time taken to reach the point from where the ball was thrown is 2.0866 s
This will also be the time it takes the ball to reach the maximum height

The initial velocity with which the rock was thrown was 20.47 m/s
Answer:
I don speak communism. Could you answer in English?
Explanation:
The distance covered is (4) times (the car's average speed during that time).
Answer:
Force = mass × acceleration.