Explanation:
At any point on the arrow's trajectory, the horizontal component of the velocity is the same. Therefore, the horizontal component of the velocity at the top of its trajectory is


The mutualism I believe. So sorry if I’m wrong
Answer:
a) speed when Jack sees the pot : 12.92 meters per second
b) height difference 163.115 meters
Explanation:
First to calculate te initial speed we use the acceleration formula:
a= v1-v0/t
Acceleration being gravity's acceleration (9.8 m/s^2)
v1 being the speed when Jill sees the pot
v0 when Jack sees it
and t the time between
Solving for v0 it would be
v1 - a*t = v0
replacing

For the second question we use the position formula setting y0 and t0 as the position and time when jack sees the pot. (and setting the positive axis downward I.E. one meter below jack would be 1m not -1m)
The formula is

replacing

Dropping it on a hard surface.