Question

W have three air carts (labeled #1, #2, and #3) on an air track. The carts are equipped with spring bumpers so that all collisions are elastic. The masses of the carts are m1 = 5m, m2 = 2m, and m3 = m. Initially, cart #1 is given a velocity to the right of magnitude v0 and the other carts are at rest. Determine the final speed of each cart.

I found the final speed of cart 1 using the formula:
((m1-m2)/(m1+m2))*(v0)
But, now I'm stuck and need help finding the speed of the last two carts.
Thanks!!!!