One positive effect of devolution is that it helps maintain a cohesive state. This means that it helps the state remained unified.
It is formed through pyroclastic rock fragments as it builds up it makes a cinder cone. I hope that helps...
Answer:
Africa, Asia, America, Australia, Antarctica
Explanation:
The earliest of civilizations were based around river valleys. This allowed them to irrigate fresh water to their crops allowing for better farming and therefore, bigger and better civilizations.
