What is the effect of pressure on speed of sound in air?

What is the effect of temperature on the speed of sound ?

The speed of sound in air is

What is the effect of amplitude, on the speed of sound in air ?

Speed of sound waves in air

(a) What is the speed of sound in air at 0^@ C in miles per hour ? (b) What is the approximate value od speed of sound in air at 20^@ C in km/s ?