There are limited amounts of resources in a general area. Some civilizations may not have the ability to produce resources that they need. That makes 2 routes:
1) cooperation: They can cooperate with another people group that lives in a different region and trade with them
2) conflict: They can attack/raid another people group in a different region for the resources
hope this helps
Answer:
I agree I think it is 90 :)
Explanation:
I'm pretty sure that it is oil because that is what most of the countries over there use it, making it a trend.
<span>The policy of eradication has caused 1.75 million acres of Amazon rainforest to be cleared.
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