Multiple Choice
The half-life of a radioactive isotope is 10,000 years.This isotope and its breakdown product do not normally occur together before molten rock cools and becomes solid.You analyze a volcanic rock and find 25 percent of the original amount of radioactive isotope remains,and 75 percent has decayed to its daughter element.How long ago did the rock solidify?
A) 2,500 years ago
B) 50,000 years ago
C) 10,000 years ago
D) 20,000 years ago
Correct Answer:
Verified
Correct Answer:
Verified
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