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Question
The half-life of a radioactive isotope is 140 days. In how many days does the decay rate of a sample of this isotope decrease to one fourth its initial decay rate?A) 35 days
B) 70 days
C) 105 days
D) 210 days
E) 280 days
Answer
This answer is hidden. It contains 1 characters.
Related questions
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For a controlled nuclear fusion reaction, one needs:
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B) high number density nand low temperatureT
C) low number density nand high temperature T
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The purpose of a moderator in a nuclear reactor is to:
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Q:
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