What is the relative rate of diffusion of a gas (molecular weight = $98$) compared to hydrogen?

The time for complete evaporation depends on which factors? Explain.

$A$ pressure cooker reduces the cooking time because:

$A$ sample of $O_2$ gas is collected over water at $23\,^oC$ and a barometric pressure of $751\,mm\,Hg$. What is the partial pressure of the $O_2$ gas in this sample? (Vapor pressure of water at $23\,^oC$ is $21\,mm\,Hg$)

At $T \ K$ and pressure $P$,the diffusion rate of an ideal gas is $120 \ mL \ min^{-1}$. What is the time taken (in sec.) for $3000 \ mL$ of this gas for diffusion at same temperature and pressure?

At a certain temperature, the time required for the complete diffusion of $200 \ mL$ of $H_2$ gas is $30 \ min$. The time required for the complete diffusion of $50 \ mL$ of $O_2$ gas at the same temperature will be: (in $min$)