Which of the following correctly describe gaseous diffusion or effusion?

1. AEffusion is the escape of gas molecules through a tiny hole into a vacuum or region of lower pressure
2. BThe rate of effusion in moles per second of a gas at pressure $p$ and temperature $T$ is proportional to $p/\sqrt{MT}$
3. CTwo gases at the same temperature and pressure with molar masses in the ratio $1:9$ have effusion rates in the ratio $3:1$
4. DThe time required for a given number of moles to effuse is proportional to $\sqrt{M}$ at fixed $p$ and $T$