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A speeding motor cyclist sees traffic j...

A speeding motor cyclist sees traffic jam ahead of him. He slows down to `36 km// hour`. He finds that traffic has eased and car moving ahead of him at `18 km//hour` is honking at a frequency of 1392Hz.If the speed of sound is `343m//s`,the frequency of the honk as heard by him will be

A

1332 Hz

B

1372 Hz

C

1412 Hz

D

1454 Hz

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