Answer:
3.25 seconds
Explanation:
The maximum height will occur when the velocity of the ball reaches zero in the air.
Velocity is given as the derivative of height, dh/dt.
The equation of height given is:

Differentiating height, h, with respect to time, t, we have:

When v = 0:

Therefore, it will take 3.25 seconds for the ball to reach maximum height.