A vapor-compression refrigeration system, using ammonia (R-717) as the refrigerant, is operating with an evaporator temperature of -20°C and condenser temperature of 30°C. It is desired to determine the influence of raising the condenser temperature to 35°C. Calculate the percent changes in

a. Refrigeration effect per kg of refrigerant flow rate

b. C.O.P.

c. Heat of compression

d. Theoretical power requirement

e. Rate of heat rejected at the condenser, anticipated due to raising the evaporator temperature.