An ideal vapor-compression refrigeration cycle, with ammonia as the working fluid, has an evaporator temperature of -25oC

Question:

An ideal vapor-compression refrigeration cycle, with ammonia as the working fluid, has an evaporator temperature of -25oC and a condenser pressure of 20 bar. Saturated vapor enters the compressor, and saturated liquid exits the condenser. The mass flow rate of the refrigerant is 3 kg/min. Determine
(a) The refrigerating capacity, in tons.
(b) The coefficient of performance (COPR) and