An astronomical telescope has an angular magnification of magnitude $5$ for distant objects. The separation between the objective and the eyepiece is $36 \, cm$ and the final image is formed at infinity. The focal length $f_o$ of the objective and the focal length $f_e$ of the eyepiece are:

  • A
    $f_o = 45 \, cm$ and $f_e = -9 \, cm$
  • B
    $f_o = 7.2 \, cm$ and $f_e = 5 \, cm$
  • C
    $f_o = 50 \, cm$ and $f_e = 10 \, cm$
  • D
    $f_o = 30 \, cm$ and $f_e = 6 \, cm$

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