150) Efficiency of a Cornot engine is given as 80%. If the cycle direction be reversed, what will be the value of COP of reversed Carnot cycle

151) Highest pressure encountered in a refrigeration system should be

152) If a heat pump cycle operates between the condenser temperature of +27°C and evaporator temperature of - 23°C, then the Carnot COP will be

153) A certain refrigerating system has a normal operating suction pressure of 10 kg/cm gauge and condensing pressure of about 67 kg/cm. The refrigerant used is

154) Aqua ammonia is used as refrigerant in the following type of refrigeration system