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Home Q & A Board Science-Related Homework Help Physics
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staedtler staedtler
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7 years ago
Element A decays into element B with a half-life of 700 million years.  You find a rock that you know was formed originally without any B present.  But the rock now contains both A and B, with the A+B portion of the rock being 1/8 A and 7/8 B.  How old is the rock?
A)   350 million years   C)   1.4 billion years
B)   700 million years   D)   2.1 billion years
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Discovering the Universe

Discovering the Universe


Edition: 7th
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discovererdiscoverer
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staedtler Author
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6 years ago
Grinning Face Exactly what I needed
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