a golfer hits a golf ball which is 30m high infront of a 20m high tree. the ball just passes over the top of the tree. what was the vertical component of the initial velocity of the ball?

Y^2 = Vo^2 + 2g*h

h = (Y^2-Yo^2)/2g
h = (0-Yo^2)/-19.6 = 30 m.
-Yo^2 = -588
Yo^2 = 588
Yo = 24.2 m/s.