Consider a two-stage cascade refrigeration system operating between -60oC and 50oC. Each stage operates on an ideal vapor-compression refrigeration cycle. The upper cycle uses R-134a as working fluid, lower cycle uses R-22. In the lower cycle refrigerant condenses at 10oC, in the upper cycle refrigerant evaporates at 0oC. If the mass flow rate in the upper cycle is 0.5 kg/s, determine (a) the mass flow rate through the lower cycle, (b) the rate of cooling in tons, (c) the coefficient of performance (COPR) and (d) the compressor power input in kW.