<u>Answer:
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The build-up of three oxygen created our ozone layer around two billion years ago.
<u>Explanation:
</u>
- 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.
The largest canyons and deepest valleys were created by moving water.
Answer:
find in this http://www.pmd.gov.pk/rnd/rnd_files/vol6_issue11/6_Effective%20Rainfall%20for%20Irrigated%20Agriculture%20Plains%20of%20Pakistan.pdf
Explanation:
Answer:
A,B,D
Explanation:
I believe that "B" is a possibly one; if not, then just A and D.
Also by examining other economy; you can learn from it, what people do and how they live their lives, same with listening to different music from there, because people listen to different music in different cultures as well.^^
Have a great day, and let me know if its correct or not, if so I will take down the answer or fix it if its wrong.
Loess and sand dunes I believe <span />