The frequency of ultrasonic waves is

The magnetic field strength of a current carrying wire at a particular distance from the axis of the wire

A stainless steel chamber contains Ar gas at a temperature T and pressure p. The total number of Ar atoms in the chamber is n. Now, Ar gas in the chamber is replaced by CO₂ gas and the total number of CO₂ molecules in the chamber is n/2 at the same temperature T. The pressure in the chamber now is p'. Which one of the following relation holds true? (Both the gases behave as an ideal gas)

Which one of the following is the correct relation between $$\mathop A\limits^o $$ and nm?