20. The answer is 1 (Precambrian)
21. The answer is 4 (Pennsylvanian)
22. The answer is 2 (Bony Fishes, Dinosaurs, and Mammals)
23. The answer is 2 (Reptiles)
Chemosynthesis is the biological conversion of one or more carbon- containing molecules.
Global temperatures will continue to rise
Ocean levels will drop. This negatively affects many coastal areas.
Prokaryotes are organisms as Bacteria or Animals.
Although Eukaryotes are the organisms that make their own food.
