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2 years ago

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An unknown radioactive element decays into non-radioactive substances. In 420 days the radioactivity of a sample decreases by 39

percent.1.What is the half-life of the element?2.How long will it take for a sample of 100 mg to decay to 46 mg?

1 answer:

julia-pushkina [17]2 years ago

3 0

Answer: Half life is 588.96 days

Anf It will take 659.81 days for a 100 mg sample to decay to 46 mg.

Explanation:

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$t$ - Time, measured in seconds.

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