If $10 \%$ of the power of a $(100 \pi) \ W$ light bulb is converted to visible radiation,then the average intensity of visible radiation at a distance of $10 \ m$ is (in $W \ m^{-2}$)

  • A
    $0.025$
  • B
    $0.01$
  • C
    $0.031$
  • D
    $0.05$

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