The half-life of $^{131}I$ is $8 \, days$. Given a sample of $^{131}I$ at time $t = 0$,we can assert that

  • A
    No nucleus will decay before $t = 4 \, days$
  • B
    No nucleus will decay before $t = 8 \, days$
  • C
    All nuclei will decay before $t = 16 \, days$
  • D
    $A$ given nucleus may decay at any time after $t = 0$

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