After five half lives what will be the fraction of initial substance

  • A

    ${\left( {\frac{1}{2}} \right)^{10}}$

  • B

    ${\left( {\frac{1}{2}} \right)^5}$

  • C

    ${\left( {\frac{1}{2}} \right)^4}$

  • D

    ${\left( {\frac{1}{2}} \right)^3}$

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