Answer: Global warming is happening because the greenhouse gases are becoming more thicker which makes more of the suns radiation (heat) stay in the earth; as a result, this is increasing the earth's temperature.
The subject is geography :)
Explanation:
Answer:
C. photosphere, convective zone, radiative zone, and core
Epithelium is the thin tissue forming the outer layer of a body's surface and lining the alimentary canal and other hollow structures.