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Question
Fluorine-18 is a radioisotope widely used in positron emission tomography to investigate brain activity. The half-life is 109.8 minutes. How long will it take for 2.75 
g of 18F to decay to 500 ng?
A) 0.288 min
B) 270 min
C) 871 min
D) 2.06 103 min
Answer
This answer is hidden. It contains 1 characters.
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