Natural gas is stored in a spherical tank at a temperature of 12°C. At a given initial time, the pressure in the tank is 108 kPa gage, and the atmospheric pressure is 100 kPa. Some time later, after considerably more gas is pumped into the tank, the pressure in the tank is 204 kPa gage, and the temperature is still 12°C. What will be the ratio of the mass of natural gas in the tank when p = 204 kPa gage to that when the pressure was 108 kPa gage?