At constant temperature and pressure,which gas will diffuse first,$H_2$ or $O_2$?

Give the formulas for the following:
$(i)$ Average speed of molecules $(u_{av})$
$(ii)$ Most probable speed $(u_{mp})$
$(iii)$ Root mean square speed $(u_{rms})$

Among the following gases,which one has the lowest root mean square velocity at $25 \ ^oC$?

What is the relationship between the most probable speed $(\alpha)$,average speed $(v)$,and root mean square speed $(u)$?

The rms velocity $u_{rms}$,mean velocity $u_{av}$ and most probable velocity $u_{mp}$ of a gas differ from each other at a given temperature. Which of the following ratios regarding them is correct?

At temperature $T$ (in Kelvin),the $rms$ velocity of $CO_2$ is $x \ cm/sec$. At what temperature (in Kelvin) will the $rms$ velocity of nitrous oxide $(N_2O)$ be $4x \ cm/sec$ (in $T$)?