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Question
Strontium-90 is produced in nuclear explosions. It can replace calcium in the bone. The half-life of 90Sr is 27.7 years. If the activity of 90Sr in the bones of an exposed person were 90 disintegrations per second, how long would it take the activity of 90Sr to decrease to 8.1 disintegrations per second?A) 96 years
B) 68 years
C) 46 years
D) 57 years
E) 75 years
Answer
This answer is hidden. It contains 1 characters.
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Q:
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