Three bulbs are filled with $CH_4$,$CO_2$,and $Ne$ as shown in the picture. The bulbs are connected through pipes of zero volume. When the stopcocks are opened and the temperature is kept constant throughout,the pressure of the system is found to be $...... \ atm$. (Nearest integer)

$A$ gas cylinder containing cooling gas can withstand a pressure of $14.9 \text{ atm}$. The pressure gauge of the cylinder indicates $12 \text{ atm}$ at $27 \,^oC$. Due to a sudden fire in the building,the temperature starts rising. The temperature at which the cylinder explodes is ............. $^oC$. (in $.5$)

The value of the universal gas constant $R$ is the same for all gases. What is its physical significance?

Calculate the weight of $CH_4$ in a $9 \ L$ cylinder at $16 \ atm$ and $27 \ ^\circ C$ in grams.

$300 \ mL$ of a gas at $27 \ ^\circ C$ is cooled to $-3 \ ^\circ C$ at constant pressure. The final volume is ................ $mL$.

Which one of the following is the correct $PV$ vs $P$ plot at constant temperature for an ideal gas? ($P$ and $V$ stand for pressure and volume of the gas respectively)