Hi there!
We can begin by finding the final VERTICAL velocity of the ball.
Use the following kinematic equation: vf² = vi² + 2ad
The ball does not have any initial velocity in the vertical direction so:
vf² = 2ad
Plug in given values:
vf² = 2(9.81)(44) = 29.38 m/s
Find the TOTAL speed using the pythagorean theorem (involving both the horizontal velocity which remains the same and vertical velocity)
v = √(21²) + (29.38²) = 36.115 m/s
