Tomas bought 3 software apps and 2 e-books for a total of $21. The two e-books cost $12. If s represents the cost of each app, the total cost of all 5 items is represented by 3 s 12 = 21. Which statement about verifying the solution for s is true? The solution is given by s = 6 because it makes the value of 3 s 12 equal to 21. The solution is given by s = 3 because it makes the value of 3 s 12 equal to 21. The solution is given by s = 9 because it makes the value of 3 s 12 equal to 21. The solution is given by s = 12 because it makes the value of 3 s 12 equal to 21.

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)