A person standing near the edge of the top of a building throws two balls A and B. The ball A is thrown vertically upward and B is thrown vertically downward with the same speed. The ball A hits the ground with a speed vA and the ball B hits the ground with a speed vB. We have
(a) vA > vB
(b) vA < vB
(c) vA = vB
(d) the relation between vA and vB depends on height of the building above the ground.
