R (approximately 8.314463 J·K−1·mol−1) is the Molar Gas Constant (universal gas constant)
γ (gamma) is the Adiabatic Index
T is the Absolute Temperature
Speed of Sound is the distance travelled per unit of time by a Sound wave as it propagates through an Air medium.
At 20 °C (68 °F), the speed of sound in air is about 343 meters per second.