Answer:
At the same time.
Explanation:
In the first case ,
intial velocity = 0
displacement = -h
acceleration = -g
Using second equation of motion,
s = ut + .5a
- h = - 0.5g
t = 
In the second case, consider only motion along y axis,
intial velocity = 0 ( all the velocity is along x axis)
displacement = -h ( height is same in both cases)
acceleration = -g
Using second equation of motion,
s = ut + .5a
- h = - 0.5g
t = 
In both cases time is same.
Hence, they will reach the ground simultaneously.