With the reference to the expression for speed of sound in any gas, show why pressure is not important in determining the speed of sound; by using the value for the gas constant R and the molecular mass of dry air, derive an expression for the speed that only depends on temperature.
Especially concerning humidity, you could discuss the composition of air in terms of monatomic, diatomic and triatomic molecules, and how this affects the gamma value; the ratio of the specific heat of gas at constant pressure, to that at constant volume. How does the percentage of water molecules in the air affect the molecular mass?
Required:
What is the effect of audio frequency on the speed of sound?
What are the relative magnitudes of the effects of temperature and humidity?