At what temperature in $^\circ C$ is the average molecular kinetic energy of any gas double that of its value at $20^\circ C$?

$A$ balloon has $5.0$ $g$ mole of helium at $7^{\circ} C$. Calculate
$(a)$ the number of atoms of helium in the balloon,
$(b)$ the total internal energy of the system.

If the temperature of a gas is increased from $27^{\circ}C$ to $927^{\circ}C$,what will be the change in its kinetic energy?

Two gases $A$ and $B$ are contained in the same vessel which is at temperature $T$. The number of molecules of gas $A$ is $N$ and the mass of each molecule is $m$. The number of molecules of gas $B$ is $2N$ and the mass of each molecule is $2m$. If the mean square velocity of the $x$-component of velocity of gas $B$ is $v^2$ and the mean square velocity of the $x$-component of velocity of molecules of gas $A$ is $u_x^2$,then $\frac{u_x^2}{v^2}$ is:

The average translational kinetic energy of ${O_2}$ (molar mass $32$) molecules at a particular temperature is $0.048 \; eV$. The translational kinetic energy of ${N_2}$ (molar mass $28$) molecules in $eV$ at the same temperature is:

$A$ gas is contained in a vessel at pressure $P_0$. If the mass of all molecules is halved and their speed is doubled,what will be the final pressure?