In a Galilean telescope,if the powers of an objective and eye lens are respectively $+1.25 \, D$ and $-20 \, D$,then for relaxed vision,the length and magnification will be

  • A
    $21.25 \, cm$ and $16$
  • B
    $75 \, cm$ and $20$
  • C
    $75 \, cm$ and $16$
  • D
    $8.5 \, cm$ and $21.25$

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