Imagine that a 1.0-kg cart traveling rightward at 1.0 m/s hits a 3.0-kg cart at rest. Afterward, the smaller car is observed to move leftward with a speed of 0.75 m/s. What is the momentum transferred to the smaller cart?

1. none; the larger cart was at rest and so had no momentum to give
   
2. none; the lighter cart gave a momentum transfer to the more massive cart, not the other way around.
   
3. 0.75 kg m/s leftward
4. 1.00 kg m/s leftward
5. 1.75 kg m/s leftward