Question

You have a sample of a radioactive material with a half-life of 5.0 years that has...

You have a sample of a radioactive material with a half-life of 5.0 years that has a current activity of 0.12 µCi.

The sample has a label on it which indicates that when it was first manufactured it had an activity of 3.84 µCi.

How long ago was the sample manufactured? (to 2 s.f and in years)

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