A radio-isotope has a half- life of 5 years. The fraction of the atoms – McqOptions

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1.	A radio-isotope has a half- life of 5 years. The fraction of the atoms of this material that would decay in 15 years will be [NCERT 1984; MP PMT 1996; MP PET 1997]
A.	1/8
B.	2/3
C.	7/8
D.	5/8
Answer» D. 5/8

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