The fall of the Roman Empire
law of gravity. everything that goes up must come down because there is a force called gravity that is pushing down on every object on the earth. hope this helps bebe:)
Answer:
The Christians met, hide and buried their dead to avoid detection and persecution in D. in underground passages and rooms called catacombs.
Explanation:
The Sahel was the last area in the northern parts of Africa, where vegetation can survive and where people were living at the time. Following the Sahel to the North one can find the Sahara desert which is a natural barrier that no invading force could trespass.