An ammonia refrigeration plant is to operate between a saturated liquid at \(313 \mathrm{~K}\) at the condenser outlet and a saturated vapour at \(283 \mathrm{~K}\) at the evaporator outlet. If the capacity of the refrigeration plant is desired to the tune of 6 tons, compute

(a) The coefficient of performance

(b) The work of compression

(c) The refrigerating effect given that Enthalpy of saturated vapour \(=1360.7 \mathrm{~kJ} / \mathrm{kg}\)

Enthalpy of saturated liquid at \(306 \mathrm{~K}=172.2 \mathrm{~kJ} / \mathrm{kg}\)

Enthalpy of superheated vapour \(=1512.2 \mathrm{~kJ} / \mathrm{kg}\).