<span>An ecosystem consists of a population of organisms and its
physical environment, and a population is made up of many different
communities of organisms. Every one of the creatures of similar species
living together that live in a particular biological system are known
as a populace The people in the populace contend with one another for
sustenance, settling space, and mates.</span>
Well it surely isn't nuclear, or electrical. It's not radiant either.. So the only answer is chemical.
Well there's Water, Earth, Fire, and Air. Not quite sure how this would be a school question. But here it is.
its b i took the quiz and got it right
