In an aqua-ammonia absorption refrigeration system of 8 TR capacity, the vapours leaving the generator are 100% pure NH3 saturated at 50C. The evaporator, absorber, condenser, and generator temperatures are 10C, 40C, 50C and 80C respectively. At absorber exit (strong solution), the concentration of ammonia in solution is x = 0.38 and enthalpy h = 20 kJ/kg. At generator exit (weak solution) x = 0.2 and h = 700 kJ/kg. Determine a) Heat added in generator; and b) C.O.P.