A 300-day old radioactive substance shows an activity of 5000 dps, 15 – McqOptions

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1.	A 300-day old radioactive substance shows an activity of 5000 dps, 150 days later its activity becomes 2500 dps. What was its initial activity?
A.	25000 dps
B.	20000 dps
C.	32000 dps
D.	5000 dps
Answer» C. 32000 dps

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