speed = wavelength x frequency
so wavelength = 24/48 = 0.5 m
same thing: wavelength = 343/392 = 0.875m
it is longitudinal wave as wave travels in a direction parallel to the direction of energy
the fire engine compresses the sound waves in front of it as it approaches; causing the sound frequency to increase i.e. higher pitch
sound travels faster through solid so cowboys can hear enemies sooner