The rest mass of an electron as well as that of a positron is $0.51 \, MeV$. When an electron and a positron annihilate, they produce gamma-rays of wavelength(s):

  • A
    $0.012 \, \mathring{A}$
  • B
    $0.024 \, \mathring{A}$
  • C
    $0.012 \, \mathring{A} \, \text{to} \, \infty$
  • D
    $0.024 \, \mathring{A} \, \text{to} \, \infty$

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