Around 1800 (plus or minus about 5 years) is when it was estimated that the world's population had reached 1 billion.
Answer:
12 Sides
Explanation:
Since an interior is 150 degrees,it's adjacent exterior angle is 30 degrees
Political geography examines interactions between political processes and human uses of the earth
* there should be water
* there should be plants(life)
* there should be atmosphere
* there should be oxygen and carbon dioxide,ect,................
