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Physics, 26.05.2021 20:20 jamesgraham577

The activity of a sample of caesium-137 is initially 40 kBq. How long will it take for the activity of the sample to fall by 30 kBq? (The half-life of caesium is approximately 30 years.)

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The activity of a sample of caesium-137 is initially 40 kBq. How long will it take for the activity...

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