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Home Q & A Board Science-Related Homework Help Geography and Earth Sciences
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naturelle naturelle
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7 years ago
Life is possible on Earth primarily because 
A)  gamma rays and X-rays reach the surface. 
B)  the ozonosphere and ionosphere shield the surface from harmful radiation. 
C)  variable gases of all types exist in the atmosphere. 
D)  ultraviolet radiation reaches the surface.
Textbook 
Geosystems: An Introduction to Physical Geography

Geosystems: An Introduction to Physical Geography


Edition: 7th
Author:
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kivlihankivlihan
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7 years ago
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naturelle Author
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#2
6 years ago
You're my superhero lol

Thank you
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