SPEED OF SOUND?

Generally speaking, the speed of sound is roughly 343m/second (767 mph) at 20°C. Speed will increase as density of the medium decreases...sounds moves more slowly through colder air.
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It's MONO MONDAY and the challenge is "Sound: The eye must learn to listen before it looks."
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Trust me....at a race track, you'd better be listening before you look or you'll likely get hit by some fast moving machine.  This fast moving machine is taking the turn at a high rate of speed....but not nearly not as fast as the speed of sound so there's plenty of time to hear it before you see it.
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There's no trouble hearing a racing motorcycle before you see it.  It's LOUD.  How loud is it?  DAMN LOUD!
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EXTRA:  I've been fooling around with making Posters in PS.  Any thoughts?
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Best in Large.