\(V = Vo + a.t\)
The ball is against the vector of gravity. Then, the gravity will be negative.
\(0 = 46,3 + (-9.8).t \\
t = \frac{46.3}{9.8} \\
t \approx 4.72\)
The ball will stop in the air after approx. 4.72 seconds. And will take the same time to hit the ground.
It will stay approx. 9.44 seconds in the air.