An R-12 vapour compression refrigeration system is operating at a condenser temperature of 40°C and an evaporator temperature of –5°C. Calculate the actual COP of the cycle. The enthalpies of R – 12 at various points of the cycle are : h₁ = 185.4 kJ/kg, h₂ = 208.0 kJ/kg, h₃ = h₄ = 74.6 kJ/kg.