A 280 days old radioactive substance shows an activity of 6000 dps, 14 – McqOptions

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1.	A 280 days old radioactive substance shows an activity of 6000 dps, 140 days later its activity becomes 3000 dps. What was its initial activity?
A.	20000 dps
B.	24000 dps
C.	12000 dps
D.	6000 dps
Answer» C. 12000 dps

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