How is momentum conserved in a newton's cradle when one steel ball hits the other?

1. both balls have momentum to start, and they share it after the collision.
2. all the momentum starts in one ball, and after the collision, they share it.
3. momentum is not conserved in the steel balls of a newton's cradle.
4. all the momentum starts in one ball, and after the collision, it is all in the other ball.

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s.part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.