Final answer:
The question asks for the isentropic efficiency of a refrigeration compressor, but calculations cannot be completed without additional thermodynamic data on R-134a.
Step-by-step explanation:
The question provided is asking about the isentropic efficiency of a compressor within a refrigeration system, particular to R-134a (a refrigerant type) being compressed from a saturated vapor at 0 degrees Celsius to a higher pressure and temperature. To compute the isentropic efficiency, we would need to refer to thermodynamic tables for the properties of R-134a at the given states and compare the actual compressor work to the isentropic compressor work. Unfortunately, without detailed refrigerant tables or specific enthalpy values provided, calculating the isentropic efficiency is not possible here.