An oxygen cylinder of volume 30 litre has 18.20 moles of oxygen. After some oxygen is withdrawn from the cylinder, its gauge pressure drops to 11 atmospheric pressures at temperature 27°C. The mass of the oxygen withdrawn from the cylinder is nearly equal to: $\\$[Given, = $\frac {100}{ 12}$ J$mol^-1 K^-1$, 12 R and molecular mass of$O_2$ = 32, 1 atm pressure = 1.01 × $10^5$N/m]