Multiple Choice
How many days are required for a radioactive sample,with a half-life of 5.7 d and an initial activity of 1.07 × 105 Bq,to decay to an activity of 100 Bq?
A) 57 d
B) 46 d
C) 68 d
D) 39 d
Correct Answer:

Verified
Correct Answer:
Verified
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