83 km/h * 2.5 hours (3:30 - 1:00) = 207.5 km
207.5 km - 15 km = 192.5 km
There are problems with the first sentence, and it's not really needed when
working with this question. So let's just take the 20 (Hz ?) frequency from
the first sentence, and ignore the rest of it for right now.
Wavelength = (speed) / (frequency) =
(331 m/s) / (20 Hz) = <em>16.55 meters</em>.
Definition: Frequency is the measurement of the number of times that a repeated event occurs per unit of time. Sound moves through a medium such as air or water as waves. It is measured in terms of frequency and amplitude. Frequency, sometimes referred to as pitch, is the number of times per second that a sound pressure wave repeats itself.
