Answer: 12 Hertz
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Work Shown:
Frequency = (velocity)/(wave length)
Frequency = (600 m/s)/(50 m)
Frequency = (600/50) s^(-1)
Frequency = 12 Hertz
Note: 1 Hertz (abbreviated Hz) is one cycle per second. One way we can define what the cycle is, is to measure from one peak of the wave to the next neighboring peak. This is what the wavelength is. So saying "12 Hz" is basically saying "12 wavelengths per second".