A refrigerator uses R-134a as its refrigerant and operates on an ideal vapour-compression refrigeration cycle between 0.14 MPa and 0.8 MPa. If the mass flow rate of the refrigerant is 0.05 kg/s, the rate of heat rejection to the environment is ________ kW. Given data: At P=0.14 MPa, h=236.04 kJ/kg, s=0.9322 kJ/kg-K (saturated vapour). At P=0.8 MPa, h=272.05 kJ/kg, s=0.9322 kJ/kg-K (superheated vapour). At P=0.8 MPa, h=93.42 kJ/kg (saturated liquid).