(a) The ball has a final velocity vector

with horizontal and vertical components, respectively,


The horizontal component of the ball's velocity is constant throughout its trajectory, so
, and the horizontal distance x that it covers after time t is

It lands 103 m away from where it's hit, so we can determine the time it it spends in the air:

The vertical component of the ball's velocity at time t is

where g = 9.80 m/s² is the magnitude of the acceleration due to gravity. Solve for the vertical component of the initial velocity:

So, the initial velocity vector is

which carries an initial speed of

and direction θ such that

(b) I assume you're supposed to find the height of the ball when it lands in the seats. The ball's height y at time t is

so that when it lands in the seats at t ≈ 6.38 s, it has a height of
