Reread the different bottle properties found underlined at the top of the first page. Which of the two properties tested is more important in making a good insulated bottle, silvered or evacuated and why? Properties: Each bottle was designed with different properties:
Bottle A: Silvered, evacuated
Bottle B: Silvered, not evacuated
Bottle C: Not silvered, evacuated
Bottle D: Not silvered, not evacuated

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)