The radioactivity of a certain radioactive element drops to 1/64 of it – McqOptions

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1.	The radioactivity of a certain radioactive element drops to 1/64 of its initial value in 30 seconds. Its half-life is [CPMT 1990, 97]
A.	2 seconds
B.	4 seconds
C.	5 seconds
D.	6 seconds
Answer» D. 6 seconds

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