Which nonmetal is extremely nonreactive, refusing to bond with other elements except under very unusual conditions created in the laboratory?

As you move from right to left on the periodic table the atomic radius fill in the blank

Why are people not able to scuba dive in the deep part of the ocean

There is one girl i like and i don't know how to tell her that, i have a feeling she knows but if she doesn't i don't want to make a fool out of myself how is one way to boost my confidence on asking her out