The resistance of a coil is $4.2\, \Omega$ at $100\,^o C$ and the temperature coefficient of resistance of its material is $ 0.004\,^o C$. Its resistance at $0\,^o C$ is ............. $\Omega$
  • A$6.5$
  • B$5 $
  • C$3$
  • D$4$
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