Question

 
A)...If this pitch were thrown horizontally, the ball would fall .809m by the time it reached home plate, 18.3m away. The acceleration of gravity is 9.81 m/s^2
How fast was the pitch
Answer in m/a

B)... A spy and an official reach the edge of a 5.4m waterfall. The spy's speed is 15 m/s and the officials' speed is 24 m/s. 
How far apart will the two vessels be when they land below the waterfall?
The acceleration of gravity is 9.8 m/s^2
Answer in units of m

Answer 1

(A) L=18.3 m,
h=0.809 m
h=gt²/2
t=sqrt(2h/g) = ....
L=vt =>

v=L/t=....
(B)
h=gt²/2
t=sqrt(2h/g) = …
L₁=v₁t =...
L₂=v₂t =....

Answer 2

Thanks but I'm still confused about the formulas could you work it for me so I can better understand how to do it?