a) a plastic bad is filled with nitrogen at atmospheric pressure and 18 degrees Celciuss. Assume that the mass of the bad is negligible and take the temperature of the outside air to be 0 degree Celcius. With the help of this "balloon" we want to lift a 56.0 kg girl off her feet. How large a volume of nitrogen (in M^3) is required?
b) if hot air is used instead of nitrogen, what is the required volume of the balloon if the air inside can be maintained at 41 degree celcius?