4) We are asked to identify the situation where the speed is greatest. Rather than using kinematics, it is simplest to think of the conservation of energy for this problem.
All the objects are thrown at the same initial velocity, and start at the same height. This means their initial potential energy and kinetic energy must be the same for every situation. Now, since all the objects end at the same height, they all have the same gravitational potential energy. This means, in order for energy to be conserved, all the situations will have the same kinetic energy just before hitting the ground.
Since all situations use the same ball, the mass must all be equal, which means the velocity just before hitting the ground must also be equal in all situations.
Answer: E
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