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Biology, 03.02.2020 03:55 helpplz5725

Apotassium-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. 25 years
b. 40 years
c. 1.25 years
d. 2.5 years

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Apotassium-40 sample starts with 50 atoms, and 1.25 billion years later, there are 25 atoms. what is...
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