Explain in an essay how the food chain works?

A food chain describes how energy and nutrients move through an ecosystem. At the basic level there are plants that produce the energy, then it moves up to higher-level organisms like herbivores. ... In the food chain, energy is transferred from one living organism through another in the form of food.  In ecology, a food chain is a series of organisms that eat one another so that energy and nutrients flow from one to the next. For example, if you had a hamburger for lunch, you might be part of a food chain that looks like this: grass rightarrow→right arrow cow rightarrow→right arrow human. But what if you had lettuce on your hamburger? In that case, you're also part of a food chain that looks like this: lettuce rightarrow→right arrow human

Explanation:

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8

there are two significant figures.