[Solved] Approximately how long would it take for a 370 GBq (10 Ci) Co-60 source to decay to 92.5 GBq (2.5 Ci)?

Q.	Approximately how long would it take for a 370 GBq (10 Ci) Co-60 source to decay to 92.5 GBq (2.5 Ci)?
A.	5.3 days
B.	5.3 years
C.	10.6 days
D.	10.6 years
Answer» D. 10.6 years

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Non Destructive Testing and Evaluation

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