Sorry that person didn’t help but your answer is
removal of vegetation, production of paper, construction production, and agricultural production
The top layers are the youngest and the farther you go down, the older they get. I’ll put it in exact order in a minute.
Photosynthesis!
Plants breath carbon dioxide and let's out oxygen.
(I don't really know, but I think it's photosynthesis)
It’s the third answer that says dead virus
