After 1.84 days, the activity of a sample of an unknown type radioactive material has decreased to 85.8% of the initial activity. What is the half-life of this material? (in days)

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  30. Chemistry Numerical

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  36. Chemistry

    A particular radioactive element has a half life of 10.0 days. How much is left after 30.0 days if the sample started with 345g?

  37. physics

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