2. Is right..... if not then go with 1
Explanation:
It is given that,
Mass of the ball, m = 0.06 kg
Initial speed of the ball, u = 56 m/s
Final speed of the ball, v = -34.5 m/s (opposite direction)
(a) Let J is the impulse delivered to the ball by the racquet. It is equal to the change in momentum of the object as :


J = -5.43 kg-m/s
(b) The work done by the racquet on thee ball is equal to the change in kinetic energy as :


W = -58.372 Joules
Explanation:
They will have not much control over their speed or rotational energy. they will carry a lot of gravitation potential energy which will get converted to kinetic energy as they fall through the atmosphere. They will reach their terminal velocity, the fastest they can travel with earth's gravity before they pull their parachute, when they use a parachute to extend their surface area, increasing wind resistance. this allows them to land safely.
Explanation:
Initial speed(u)= 0 m/s (Ball is dropped)
time(t)= 0.75 s
acceleration(a)= 10 m/s² (gravity)
Final speed(v)= u+at
v=0+(10)× 0.75
v=7.5 m/s
Speed is 7.5 m/s