Answer: Final speed,Vf= -4.5m/s
It is the same speed but in opposite direction,coming down against gravity.
Step-by-step explanation:
Calculating distance,d= (Vf^2-Vo^2)/2g
d=(0-4.5^2)/(2×9.8)
d= -20.25/19.6
d= -0.053m
Vf^2=Vo^2 + 2gd
Vf= Sqrt(0 +2×9.8(×-0.053))
Vf=V=-4.5m/s