If a gas is expanded at constant temperature,which of the following is true?

The mass of molecule $A$ is half the mass of molecule $B$. The $rms$ speed of $A$ is twice the $rms$ speed of $B$. If the number of molecules in samples of $A$ and $B$ are equal,what is the ratio of the pressures of samples $A$ and $B$ in separate containers of equal volume?

The transport of matter in the absence of bulk flow is known as:

$A$ $He$ atom is twice as heavy as a hydrogen molecule. At $25\,^oC$,the kinetic energy of a $He$ atom is:

According to the kinetic molecular theory of gases, the average kinetic energy of gas molecules:

The kinetic energy of $4 \ mol$ of $N_2$ gas at $127 \ ^oC$ is ............. $cal$.