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A stationary source emits sound waves of frequency 500 Hz. Two observers moving along a line passing through the source detect sound to be of frequencies 480 Hz and 530 Hz. Their respective speeds are, in ms –1 , (Given speed of sound = 300 m/s)

1. 12, 16
2. 12, 18
3. 16,14
4. 8, 18

Correct answer: 12, 18

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