Multiple Choice
In an unweathered sample of igneous rock,the ratio of an unstable isotope to its stable daughter isotope is 1:15.If no daughters were present at the time the rock cooled below closure temperature,and the half-life of the isotope is 50 million years,how old is the rock? 
A) 200 million years
B) 400 million years
C) 750 million years
D) 1 billion years
Correct Answer:
Verified
Correct Answer:
Verified
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