The speed of sound in air is not affected by change in :

1. temperature
2. moisture
3. pressure
4. density

The speed of sound in a gas is related to temperature (in Kelvin) as :

1. directly proportional to temperature.
2. directly proportional to the square root of temperature.
3. inversely prtiportional to temperature.
4. inversely proportional to the square root of temperature.

Factors affecting the speed of sound are :

1. temperature
2. density
3. pressure
4. only (a) and (b)