Define
h = height (m) at time t (s).
Because the ball stays in the air for 60 s, the ball reaches a maximum height after 30 s, when the upward velocity is zero.
Note that
g = 9.8 m/s², the acceleration due to gravity.
Let v = the vertical launch velocity. Then
v - (9.8 m/s²)*(30 s) = 0
v = 294 m/s
Also, the maximum height, H, is
H = (294 m/s)*(30 s) - (1/2)*(9.8 m/s²)*(30 s)²
= 4410 m
Answer: 4410 m