A radioactive sample is a-emitter with half life 138.6 days is observe – McqOptions

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1.	A radioactive sample is a-emitter with half life 138.6 days is observed by a student to have 2000 disintegration/sec. The number of radioactive nuclei for given activity are
A.	3.45 ´ 1010
B.	1 ´ 1010
C.	3.45 ´ 1015
D.	2.75 ´ 1011
Answer» B. 1 ´ 1010

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