Refrigerant R-134a enters a compressor at 0.14 MPa and -10°C and exits at 0.8 MPa and 50°C. Take surrounding conditions Po=95 kPa and T₁ = 20°C. Calculate the exergy change of the refrigerant. as A) 36 kJ/kg B) 37 kJ/kg C) 35 kJ/kg D) 38 kJ/kg A piston-cylinder device contains steam at 60 psia and 320°F, and the temperature is increased to 400°F through heat transfer. If the mass of the steam in the device is 15 lbm and the weight of the piston is constant throughout the process. Calculate the work done during the process in Btu. A) 144.64 Btu B) 521.1 Btu C) 130.275 Btu D) 97 Btu