I got an exam tomorrow, and since I missed the last week, I don't really know how to solve questions like these:(adsbygoogle = window.adsbygoogle || []).push({});

2. Relevant equations

1 gramm of Ra-226 radiates 3,7*10^10 alpha-particles in a second. Find out the half-life period of Ra-226.

We produce a radioactive Cu-64 and seal it. After 20 days, the activity is 20 Bq. What was the mass in gramm of the Cu-64 when we produced it?

Answers and explanations would be greatly appreciated,

Thanks,

Pear

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# How do you solve this?

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