Answer:
the power of energy drink water.high energy verses.
The correct answer is Mollusks, Echinoderms, Chordates, and Annelids.
This is basically how evolution works, at a certain point in the past,
there was a transitional organism that eventually developed into
roundworms and the other part of his species that was exposed to other
things evolved into other transitional organisms who evolved eventually
into these 4 groups.
I'm not exactly sure what specifically you are asking for in relationship to balancing equations, but I have some examples with working out so you can examine them and try to go through the steps with them.
Hope this helps! <3