Awave has a wavelength of 125 meters is move a distance of 300 m in 15s. what is its frequency?

   Frequency of any wave  =  (speed) / (wavelength)

                                           = (300m / 15s)  /  (125m)

                                           =  (300m)  /  (15s x 125m)

                                           =      (300) / (15 x 125)    (m/s-m)

                                           =             0.16 / sec  =  0.16 Hz . 

The answer is a 0.64 volts