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Home Q & A Board Science-Related Homework Help Physics Astronomy
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adreamer adreamer
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7 years ago
Suppose that there are 10 billion (10,000,000,000,000) habitable planets in our galaxy, that 1 in 5 habitable planets has life, that 1 in 1000 planets with life has at some point had an intelligent civilization, and that 1 in 1000 civilizations that have ever existed is in existence now. How many civilizations would exist at present?
A) 200,000
B) 2,000,000
C) 20,000
D) 20,000,000
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Life in the Universe

Life in the Universe


Edition: 4th
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19Clyde19Clyde
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7 years ago
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adreamer Author
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7 years ago
Thanks for your help!!
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This calls for a celebration Person Raising Both Hands in Celebration
KaylenePig
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2 hours ago
Smart ... Thanks!
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