What will be the average value of energy for a monoatomic gas in thermal equilibrium at temperature $T$?

$\gamma_{A}$ is the specific heat ratio of a monoatomic gas $A$ having $3$ translational degrees of freedom. $\gamma_{B}$ is the specific heat ratio of a polyatomic gas $B$ having $3$ translational,$3$ rotational degrees of freedom,and $1$ vibrational mode. If $\frac{\gamma_{A}}{\gamma_{B}} = (1 + \frac{1}{n})$,then the value of $n$ is . . . . . . .

How many rotational degrees of freedom does a rigid diatomic molecule have?

For a triatomic gas molecule,if the degrees of freedom for translation,rotation,and vibration are considered,then $C_P/C_V = ?$

The gases carbon monoxide $(CO)$ and nitrogen $(N_{2})$ at the same temperature have kinetic energies $E_{1}$ and $E_{2}$ respectively. Then

What will be the average value of energy along one degree of freedom for an ideal gas in thermal equilibrium at a temperature $T$? ($k_{B}$ is Boltzmann constant)