Convert from mach to speed of sound [air]

Unit Definition (mach)
The Mach is a measure of velocity relative to the speed of sound. The precise speed of sound varies with the density and temperature of the atmosphere, although at 0 °C (at 1atm.) the speed of sound is 331.6 m/s. The mach speed is important to the control of an aircraft, especially at speeds close to or exceeding Mach 1.0. The unit is named after the Austrian physicist Ernst Mach.

Unit Definition (speed of sound [air])
The speed of sound c (from Latin celeritas, "velocity") varies depending on the medium through which the sound waves pass. It is usually quoted in describing properties of substances (e.g. see the article on sodium).