Which type of bond will form between these elements? * WHICH BONO
Covalent
Metallic
lonic
Please I need the answer I had a stomach virus and didn’t get to study for my test

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.