A shopping cart of mass m, moving at a velocity of v to the right, running into a second shopping cart, of mass 3 m, which is at rest. After the collision, if the first shopping cart is moving at a velocity of v/2 towards the left, how much impulse did the second cart deliver to the first?

a. None. The heavier cart was at rest and had no momentum to give to the lighter one.
b. mv to the left
c. mv/2 to the left None.
d. The lighter cart gave momentum to the heavier cart, not the other way around.
e. 3mv/2 to the left