40, A typical hot air balloon has a volume of 100,000 cubic feet [m]. Air has a specific gravity of 000129 and a molecular mass of 28.97 grams per mole [g/mol] at one atmosphere [atm) and 533 degrees Rankine [ R. What is the weight in units of pound-force [Ibl of the air in such a balloon? 40, A typical hot air balloon has a volume of 100,000 cubic feet [m]. Air has a specific gravity of 000129 and a molecular mass of 28.97 grams per mole [g/mol] at one atmosphere [atm) and 533 degrees Rankine [ R. What is the weight in units of pound-force [Ibl of the air in such a balloon