A Rock Sample Contains 1/2 Microgram of the Parent Radioactive

question 127

Multiple Choice

A rock sample contains 1/2 microgram of the parent radioactive isotope Uranium-235 and 1/2 microgram of its daughter isotope Lead-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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James Spradley

An influential American anthropologist known for his work on ethnography and qualitative research methods.

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