The coefficient of performance of a refrigerator is 5. If the temperature inside freezer is -20oC, the temperature of the surroundings to which it rejects heat is:

Coefficient of performance of refrigeratorCOP = TLTH-TLwhere TL→ lower temperature and TH → Higher temperatureSo,     5 = TLTH-TL⇒TH = 65TL = 65(253) =  303.6 K. Therefore  tH =30.60 C ≃310C