The root mean square velocity of a gas molecule of mass $m$ at a given temperature is proportional to

Two vessels having equal volume contain molecular hydrogen at $1 \text{ atm}$ and helium at $2 \text{ atm}$ respectively. If both samples are at the same temperature,the mean velocity of hydrogen molecules is

The following graph shows two isotherms for a fixed mass of an ideal gas. The ratio of $r.m.s.$ speed of the molecules at temperatures $T_2$ and $T_1$ is

For which gas is the $rms$ velocity maximum?

To what temperature should the hydrogen at $327^{\circ} C$ be cooled at constant pressure,so that the root mean square velocity of its molecules becomes half of its previous value (in $^{\circ} C$)?

$A$ sample contains a mixture of helium and oxygen gas. The ratio of the root mean square speed of helium to oxygen in the sample is: