You are playing with carts in lab. You carefully attach a spring-loaded plunger on the end of a 0.25kg cart and push it at a velocity of +20m/s relative to the Earth. It then collides with a 0.50kg cart travelling at +10m/s relative to the Earth. The collision triggers the plunger, causing an explosive collision between them. If you know the system's kinetic energy in the Earth's reference frame is increased by 25% in the collision, what are the final velocities of the two carts?