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Home Q & A Board Science-Related Homework Help Physics
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symbo symbo
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7 years ago
For an astronomer, what is the “water hole”?

(a)   A range of noise-free frequencies between the microwave emission lines of hydrogen and hydroxyl
(b)   A range of noise-free frequencies near the 21-cm emission line of hydrogen
(c)   A gathering place for gnus
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Discovering the Universe

Discovering the Universe


Edition: 7th
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discovererdiscoverer
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symbo Author
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7 years ago
Thanks
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Yesterday
Thank you, thank you, thank you!
avance37
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2 hours ago
Just got PERFECT on my quiz
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