6. A 1.00 ft³ well insulated rigid can initially contains

refrigerant 134a at 90 psia and 30°F. Now a crack

develops in the can and the refrigerant starts to leak

out slowly. Assuming the refrigerant remaining in the

can has undergone a reversible, adiabatic process,

determine the final mass in the can when the pressure

drops to 15 psia. [MO1]