Ecological Pyramids are used to explain energy flow in a food web. They all need trophic levels. What are the trophic levels?

A trophic level is the group of organisms within an ecosystem which occupy the same level in a food chain. Like producer, consumer, and decomposer

Explanation:

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

layer 3 is younger than layer 6.