A 90 kilogram fullback running north at 10 meters per second is tackled by a 120 kilogram linebacker running south at 4 meters per second in a perfectly inelastic collision. Which of the following is the velocity in meters per second of the players after the collision?

W) 3 south

X) 3 north

Y) 2 south

Z) 2 north
Z) 2 NORTH