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Home Q & A Board Science-Related Homework Help Physics
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doit_the_clown doit_the_clown
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7 years ago
Seventy percent of all species living on land and 90% of all species living in the oceans disappeared at the end of the Permian era, 250 million years ago. What is believed to have been the cause of this massive extinction?
A)   Global warming from volcanic gases released during the breakup of the Gondwanaland supercontinent
B)   A nearby supernova (the explosion and total destruction of a star)
C)   A devastating impact by an asteroid
D)   A “snowball Earth” episode in which global cooling caused the Earth's ocean surfaces to freeze and glaciers to cover the continents
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Discovering the Universe

Discovering the Universe


Edition: 7th
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Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.

Albert Einstein
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papachulopapachulo
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7 years ago
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doit_the_clown Author
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7 years ago
Smart ... Thanks!
Lourd Jenkins
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Yesterday
Brilliant ツ
avance37
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2 hours ago
This calls for a celebration Person Raising Both Hands in Celebration
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