A. Why don't the lost atoms come back? los
I

Rubbing

Explanation: The lost atoms never come back because after rubbing, the molecules are shaking back and forth faster than they were billions of atoms. When molecules break apart or come together, that's called a nitrogen and oxygen molecules are lost this way too, but since their average velocity is so simplicity , that is missed by people who don't study physics.

wher is the rest of the question

the answer is c.the valence of the atoms combine .