The U.S economy produce 20% of the world's output
Northern hemisphere, south eastern part of the country
coal, copper, lead, iron, natural gas, timber, bauxite, and uranium.
<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.
<span>The angular size of the moon in our sky is almost exactly the same as the angular size of the sun in our sky. This can be seen and noticed during a full eclipse, by some remarkable coincide, the Earth's moon, from our point of view, is at the perfect distance from Earth in relation to the sun, to have almost matching sizes, allowing for the complete blocking of light when the moon and sun align.</span>
