(Solved): A projectile is launched from the top of a 20-m tall cliff towards another cliff that is 40-m tall a ...

A projectile is launched from the top of a 20-m tall cliff towards another cliff that is 40-m tall and
100-m away. If the projectile is launched at an angle of 50°:
a. At what speed must it be launched to just barely reach the other cliff?
b. What is the maximum height of the projectile, and at what horizontal position will it reach
this maximum height?