Which method of heat transfer transmits heat from the lower layers of air to the upper layers of air as the lower layers of air warm up and rise and replace the upper layers of air that cool off and sink down?

Convection

Explanation:

The method of heat transfer that allows heat to rise via vertical transport of heated part of a fluid (gas or liquid) and replace the fluid upper layers is called "convection"

convex lenses are thicker at the middle. rays of light that pass through the lens are brought closer together (they converge). a convex lens is a converging lens. when parallel rays of light pass through a convex lens the refracted rays converge at one point called the principal focus.

i would think it's food chain