The rest mass energy of an electron is $0.51 \ MeV$. If this electron is moving with a velocity of $0.8 \ c$ (where $c$ is the velocity of light in vacuum),then the kinetic energy of the electron is ........... $MeV$.

  • A
    $0.28$
  • B
    $0.34$
  • C
    $0.39$
  • D
    $0.46$

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