Refraction is the bending of light (it also happens with sound, water and other waves) as it passes from one transparent substance into another. This bending by refraction makes it possible for us to have lenses, magnifying glasses, prisms and rainbows. Even our eyes depend upon this bending of light. Hope this helps!
The negative side of another magnet
Empirical formula is the simplest way the molecular formula can be wrote so here 7 goes into all of these so it would be CH2O
The answer is zero!
let me know if you need help with anything else! :)