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Question
The number of disintegrations per minute (dsm) of a sample of iodine-133 is measured at 5.5 102 dsm. When the sample is measured 295 minutes later, the number of disintegrations has decreased to 4.7 102 dsm. What is the half-life of iodine-133?
A.5.7 10-4 m.
B.2.6 m.
C.1.3 103 m.
D.3.9 102 m.
E.9.7 104 m.
Answer
This answer is hidden. It contains 2 characters.
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Q:
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