Consider Massive Gliders That Slide Friction-Free Along a Horizontal Air

Multiple Choice

Consider massive gliders that slide friction-free along a horizontal air track.Glider A has a mass of 1 kg,a speed of 1 m/s,and collides with Glider B that has a mass of 5 kg and is at rest.If they stick upon collision,their speed after collision will be

A) 1/4 m/s.
B) 1/5 m/s.
C) 1/6 m/s.
D) 1 m/s.
E) none of these