A policeman on duty detects a drop of $10 \%$ in the pitch of the hom of motion of car as it crosses him. If the velocity of sound is $330 \,m / s$. Calculate the speed of the car ........... $m / s$
  • A$36.7$
  • B$20.4$
  • C$18.6$
  • D$16.4$
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