They share four electrons, two from each oxygen atom
A Chemical change is any form of chemical reaction changing the state of the matter involved. When you fry an egg, you are making a reaction between the heat and the chemicals that make up the egg. Therefore once you have fried that egg, you have completed a chemical reaction. This is why it's a chemical change when you fry an egg.
For sediments to become a sedimentary rock, it usually undergoes burial, compaction, and cementation. (Hope that helps)
Answer:
Thorium-234 option a .......
I believe there are 3 significant figures B.
