Change in Kinetic Energy of an Elastic Collision

The six situations below show mass (m) and velocity (v) information for two carts prior to a collision.  Assume all collisions are elastic and any motion to the right is considered positive.   Rank from the greatest to the least on the basis of the change in kinetic energy for each collision.


Greatest   1____  2_____  3_____  4_____  5_____ 6______ 7_____ 8_____Least

Or, all changes in kinetic energies are the same for each collision.  ________  

Please carefully explain your reasoning.

 
How sure were you of your ranking?  (circle one)
Basically Guessed Sure
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