At what temperature will the average speed of $CH_4$ molecules have the same value as $O_2$ has at $300 \ K$ ........... $K$

In which of the following pairs do the gaseous species diffuse with the same rate of diffusion under similar conditions of temperature and pressure?

At what temperature (in $K$) is the $rms$ velocity of $SO_2$ molecules equal to the $rms$ velocity of $O_2$ molecules at $27^{\circ} C$?

Which of the following is correct regarding molecular speeds?

Initially,the root mean square $(rms)$ velocity of $N_2$ molecules at a certain temperature is $u$. If this temperature is doubled and all the nitrogen molecules dissociate into nitrogen atoms,then the new $rms$ velocity will be:

At what temperature will the $RMS$ velocity of sulphur dioxide $(SO_2)$ molecules at $400 \ K$ be the same as the most probable velocity of oxygen $(O_2)$ molecules (in $K$)?