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Elis [28]
3 years ago
6

A potassium-40 sample starts with 50 atoms, and 1.25 billion years later, there are 25 atoms. What is the half-life of potassium

-40?
A. 2.5 billion years
B. 25 years
C. 40 years
D. 1.25 billion years
Chemistry
1 answer:
guapka [62]3 years ago
5 0
D. 1.25 billion years
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