Which of the following statements best explains why third-degree burns are less painful than second-degree burns?
a. third-degree burns are not as severe as second-degree burns.
b. third-degree burns result in nerve damage, which reduces feeling.
c. blisters are a mechanism of second-degree burns to alleviate pain.
d. second-degree burns result in scarring.

4r-134a enters the condenser of a residential heat pump at 800 kpa and 50°c at a rate of 0.022 kg/s and leaves at 750 kpa subcooled by 3°c. the refrigerant enters the compressor at 200 kpa superheated by 4°c determine (a) the isentropic efficiency of the compressor, (b) the rate of heat supplied to the heated room, and (c) the cop of the heat pump. also, determine (d) the cop and rate of heat supplied to the heated room if this heat pump operated on the ideal vapor-compression cycle between the pressure limits of 200 and 800 kpa. (0.757, 4.37 kw, 5.12, 6.18, 3.91 kw)