What happens in a convection cell?

a. cooler, more dense material sink while warmer, less dense material rises.

b. cooler, less dense material sinks, while cooler, more dense material rises.

c. warmer, less dense material sinks, while cooler, more dense material rises.

The correct option is A. Cooler, more dense material sink while warmer, less dense material rises.

Explanation:

Convection can simply be described as the transfer of heat energy among molecules or substances. Convection will occur if molecules of liquid or gas are given rough supply of heat. Hot liquids or gases would have the following properties:

Whereas the cooler molecules will have the following properties:

The corals and algae have a mutualistic relationship. The coral provides the algae with a protected environment and compounds they need for photosynthesis. In return, the algae produce oxygen and help the coral to remove wastes.

Explanation:

I dunno if this is right I may be a little off :}