Understanding the Problem

* The ball goes up, reaches its highest point, and then comes back down to its starting position. This means the time it takes to go up is equal to the time it takes to come down (2.48 seconds each way).

* We're dealing with vertical motion under the influence of gravity.

Key Concepts

* Acceleration due to gravity (g): -9.8 m/s² (negative because it acts downward)

* Final velocity (vf): The final velocity at the highest point is 0 m/s.

* Time (t): We know the time it takes for the ball to go up (2.48 s).

Solving the Problem

We can use the following kinematic equation:

vf = vi + at

where:

* vf = final velocity

* vi = initial velocity

* a = acceleration (due to gravity, g)

* t = time

Let's plug in the values:

0 = vi + (-9.8 m/s²) * 2.48 s

Solving for vi:

vi = 9.8 m/s² * 2.48 s

vi = 24.3 m/s

Therefore, the initial velocity of the ball was 24.3 m/s.