The air behind a warm front is cold and dry

"The air behind a warm front is cold and dry."
The statement is TRUE.

Warm and moist air invasive on a mass of cooler or drier air ends up in a warm front. warm and moist air is, of course, less dense than cold and dry air and can simply "ride" over the highest of cool air.

As a metabolic heat.

Explanation:

The loss of energy from one trophic level to the next in a food chain occurs because energy is lost in the form of heat when the organisms from one trophic level are consumed by organisms from the next level. Only 10% of energy is transferred from one trophic level to another while the remaining 90% energy is lost in the form of heat energy in the ecosystem.