The only one I know for sure is Mass is always conserved In a Chemical reaction.
Answer:
Explanation:
The water table or phreatic surface
The answer is 2 pairs. The carbon atom has 4 electrons and oxygen atom has 6 electrons. The purpose of shared electron is to get 8 electrons at the outer layer. So the carbon atom needs to share 4 electrons which is 2 pairs with oxygen to be stable.
The answer is Index fossils its the only answer it could be
