Question: - Plants and animals long ago died - They are buried under layers of soil - Pressure builds over time - The remains liquefy What might be the last step of the process?
Answer: The carbon atoms rearrange to become a new substance.

Question: - Spores are dispersed into the air by a mature mushroom - The spores fall to the ground - The spores germinate - The spores begin to grow mycelium - The mycelium begin to sprout a bud What might be the last step of the process?
Answer: A new mushroom is formed.

Question: - People breathe and expel carbon dioxide - Engines produce carbon dioxide - Living things produce waste - Waste decomposes - Decomposition produces methane - Water evaporates - Water vapor joins the atmosphere What might be the last step of the process?
Answer:
Carbon dioxide, water vapor and methane are greenhouse gases