A Boy on the Edge of a Vertical Cliff 20

Multiple Choice

A boy on the edge of a vertical cliff 20 m high throws a stone horizontally outwards with a speed of 20 m/s. It strikes the ground at what horizontal distance from the foot of the cliff?
Use g = 10 m/s²

A) 10 m
B) 40 m
C) 50 m
D)
E) none of these