A motor car blowing a horn of frequency $124\,vib/sec$ moves with a velocity $72\, km/hr$ towards a tall wall. The frequency of the reflected sound heard by the driver will be .... $vib/sec$ (velocity of sound in air is $330\, m/s$)
  • A$109$
  • B$132$
  • C$140$
  • D$248$
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