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प्रश्न
A radioactive substance decays to 1/16th of its initial mass in 40 days. The half-life of the substance, in days, is:
पर्याय
20
10
5
2.5
उत्तर
A radioactive substance decays to 1/16th of its initial mass in 40 days. The half-life of the substance, in days, is 5.
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