8–34E Saturated R-134a vapor enters a compressor at 68F. At compressor exit, the specific entropy is the same as that at the inlet, and the pressure is 80 psia. Determine the R-134a exit temperature and the change in the enthalpy of R-134a.

Apipe with an outside diameter of 15 cm is exposed to an ambient air and surrounding temperature of -20°c. the pipe has an outer surface temperature of 65°c and an emissivity of 0.85. if the rate of heat loss from the pipe surface is 0.95 kw per meter of length, the external convective heat transfer coefficient (h) is: (a) 12.5 w/m"k (b) 18.6 w/mk (c) 23.7 w/mk (d) 27.9 w/mk (e) 33.5 w/mk