Which labels best complete the diagram? X: High resistance Y: Low resistance Z: Flow of electrons X: Low resistance Y: Flow of electrons Z: High resistance X: Flow of electrons Y: High potential energy Z: Low potential energy X: Low potential energy Y: High potential energy Z: Flow of electrons

How is it possible for someone to put an ear to a wall and hear someone in the next room?     a.sound waves can travel though solids.    b.the waves travel from room to room via air.    c.there must be some air in the wall so the sound can travel through it.    d.sound waves change to electromagnetic waves and then back again.