Convection currents occur: a. Only in liquids
b. When a dense substance is warmer than a less dense substance
c. In both liquids and gases
d. Weakly in solids

U. life is what you go through to become a better person. it makes you stronger, wiser, and more creative. it can be hard but its ok. because i believe everyone was put here for a reason. whether or not you know that reason you should always look towards the future and trust in god for a better tomorrow.be safe and blessed