Wax is a nonpolar substance. in which type of substance is it the most soluble? a. a cold nonpolar solvent b. a cold polar solvent c. a hot nonpolar solvent d. a hot polar solvent

Probably if the wax is in a molten state a hot non-polar solvent would be best. Heat  vegetable oil would be the best way to dissolve the molten wax.

Second question.

I actually think the ice forms on the top because it is less dense than the water. Good thing too. Fish would be frozen solid in winter if ice sank rather than floated as most other substances behave.

one negative thing it that it can kill water animals. another negative thing is it can cause the destruction of ecosystem. one way water pollution can be reduced is to conserve energy.