We have the next formula to calculate the kinetic energy

where m is the mass and v is the velocity
For the kinetic energy of ball 50 kg traveling at 10 m/s

For the kinetic energy of ball 50 kg traveling at 20 m/s

A 50 kg ball traveling at 20 m/s would have 4 times kinetic energy.
For kinetic energy of the ball 50 kg at 5m/s

A 50 kg ball traveling at 5 m/s would have 4 times less kinetic energy
For the person 50kg falling 10 m/s

A 50 kg person falling at 10 m/s would have the same kineticenergy}.
The solution is
A 50 kg ball traveling at 20 m/s would have 4 times more kinetic energy.
A 50 kg ball traveling at 5 m/s would have 4 times less kinetic energy.
A 50 kg person falling at 10 m/s would have the same kinetic energy.