Solve the all parts of following problem given below:
Problem: An attacker at the base of a castle wall 3.60 m high throws a rock straight up with speed 4.00 m/s from a height of 1.60 m above the ground.
Part A: If so, what is its speed at the top? If not, what initial speed must it have to reach the top?
in m/s
Part B: Find the change in speed of a rock thrown straight down from the top of the wall at an initial speed of 4.00 m/s and moving between the same two points.
in m/s
Do not copy and paste from Google, explain your answer clearly.