A region that could be farmed and maintained suitable for human life
<span>It was called that, but that is wrong. Actually, what is now called the Middle East was where the first Civilizations started. Sumer, Akkadia, and Babylon were the first three and they existed long before the area of Italy was civilized. It is even possible that Greece was civilized earlier than Rome. If you ask a Greek, they will say it is so anyway.
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Germany! I hope this helps ya out.
<u>Answer:
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The build-up of three oxygen created our ozone layer around two billion years ago.
<u>Explanation:
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- The ozone layer is a part of the stratosphere which is located right after the troposphere in the atmosphere of the Earth.
- The ozone gas is made up of the abundance of three oxygen molecules combining with the ultraviolet radiation emitted by the Sun.
- The development of the ozone layer happened around two billion years ago when the oxygen concentration levels on the planet began to rise slowly and gradually.
-4x^2-4xy+6y^2 hope this helps