Answer:
The Total Momentum before and after collision remains the same.
Step-by-step explanation:
Note that the balls have the same masses.
A moving cue ball has an initial momentum. After every collision with another stationary ball, the momentum, which is the product of their mass and velocity, of the balls is conserved. This simply means that the total momentum before the collision is the same as the total momentum after the collision.
This also means that the energy must be conserved as well. The balls cannot fling away from each other with more energy than you give them.