Five kg of R-22 refrigerant at 3 bar and saturated vapor is contained in a closed, rigid tank. A process cools the R-22 to a temperature of -30 C. (Hint: Think of what remains constant during a process in a closed, rigid tank.) a) What is the specific volume of this R-22 initially? b) What is the quality of this R-22 after the cooling? c) What is the internal energy U after the cooling?