An R-134a refrigerator of 4 TR capacity works on the cycle shown on the p-h diagram in Figure 3. The refrigerant leaves the evaporator as saturated vapour (state 1) and the condenser as saturated liquid (state 3). The compressor has an isentropic efficiency of 80 %; the isentropic end-state enthalpy h_{2s} and the saturation data at 0.14 MPa are given on the figure. Take 1 TR = 3.5 kW. Determine (a) the dryness fraction of the refrigerant entering the evaporator (answer as a fraction), (b) the mass flow rate of refrigerant (in kg/s) and (c) the actual COP of the refrigerator (answer as a number).