Two Objects of the Same Mass Move Along the Same

Multiple Choice

Two objects of the same mass move along the same line in opposite directions.The first mass is moving with speed v.The objects collide,stick together,and move with speed 0.100v in the direction of the velocity of the first mass before the collision.What was the speed of the second mass before the collision?

A) 1.20v
B) 10.0v
C) 0.900v
D) 0.800v
E) 0.00v