For an ideal gas obeying Boyle's Law,which of the following is correct? ($K$ is a constant)

$A$ gas at a pressure of $2 \ atm$ is heated from $25^{\circ} C$ to $323^{\circ} C$ and simultaneously compressed to $\frac{2}{3}$ of its original volume. What is the final pressure (in $atm$)?

The density of a gas at $27\,^oC$ and $1\, atm$ is $d$. At constant pressure,at which of the following temperatures will its density become $0.75\, d$?

At $273\,K$,$Pd$ vs $P$ is plotted for various gases $1, 2, 3, 4$. Assuming ideal behaviour for four gases $N_2, He, CO_2$ & $H_2$. The correct combination is [$P$ denotes pressure in atmosphere & $d$ denotes density in $g/L$]

Volume of $0.5 \ mole$ of a gas at $1 \ atm$ pressure and $273 \ K$ is ............. $litres$.

The same gas is filled in two containers $X$ and $Y$. If the pressure,volume,and absolute temperature of the gas in container $X$ are three times those in container $Y$,and the mass of the gas in $X$ is $m \, g$,what will be the mass of the gas in $Y$?