A radioactive substance has a half-life of 60 minutes. After 3 hours, – McqOptions

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1.	A radioactive substance has a half-life of 60 minutes. After 3 hours, the fraction of atom that have decayed would be [BHU 1995; 2000]
A.	12.5%
B.	87.5%
C.	8.5%
D.	25.1%
Answer» C. 8.5%

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