A 100-gallon insulated tank is filled with saturated propane at 50o C, where the vapor part occupies 30% of the tank volume (the rest is liquid). A valve at the top of the tank is opened and saturated vapor is slowly withdrawn until the temperature inside drops to 30o C, during which the valve is closed. The mixture left after releasing the vapor is still a saturated mixture. Report the following:

a. the total amount of propane withdrawn (in kg)

b. final quality of the mixture