Superheated refrigerant (134a) enters a throttling valve at a pressure of 0.9 MPa and a temperature of 140 degrees Celsius. The enthalpy of the fluid as it exits the throttling valve (in kJ/kg) is:
a) This cannot be determined without additional information.
b) The enthalpy remains constant across the throttling valve.
c) The enthalpy decreases as the refrigerant expands across the throttling valve.
d) None of the above.
