Answer:
The maximum height is reached after 3.75 seconds.
Explanation:
Assuming the deceleration due to gravity is unaided by air resistance, gravity causes the ball to lose vertical speed at the rate of 32 ft/s every second. The initial vertical speed of 120 ft/s will decline to zero when t satisfies ...
... 120 ft/s - (32 ft/s²)t = 0
... (120 ft/s)/(32 ft/s²) = t = 3.75 s
The ball will not go any higher after its vertical speed is zero.