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Home Q & A Board Science-Related Homework Help Physics Astronomy
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hermiz hermiz
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6 years ago
A rock sample contains 1/2 microgram of the parent radioactive isotope U-235 and 1/2 microgram of its daughter isotope Pb-207. If the half-life of this decay is 700 million years, how old is this rock?
A) 1400 million years
B) 2100 million years
C) 700 million years
D) 350 million years
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Life in the Universe

Life in the Universe


Edition: 4th
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Life in the Universe, 4/E (Bennett, Shostak)
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DonskoyDonskoy
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hermiz Author
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6 years ago
Helped a lot
nsak
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Yesterday
This helped my grade so much Perfect
branbran2k16
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2 hours ago
Smart ... Thanks!
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