The speed of sound in air in fact depends on the temperature of the air.
a) At 0⁰C, the speed of sound in air is 331.5 m/s.
b) For every Celsius degree above 0⁰C, the speed increases by 0.6 m/s.
c) For every Celsius degree below 0⁰C, the speed decreases by 0.6 m/s.