What is the molar volume of a gas? What is its value taken as?

Which of the following plots is hyperbolic at constant temperature?

$A$ 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 volume-temperature graphs of a given mass of an ideal gas at different constant pressures are shown below. What is the correct order of pressures?

$A$ gas occupies $11.2 \ dm^3$ at $105 \ kPa$. What is the volume if pressure is increased to $210 \ kPa$ (in $dm^3$)?

Containers $A$ and $B$ contain the same gas. The pressure,volume,and temperature of the gas in $A$ are twice the corresponding values of the gas in $B$. The ratio of the number of molecules of gas in $A$ to that in $B$ is ...