3. If the door of a refrigerator is kept open, then which of the following is true

(a)  Room is cooled

(b)  Room is heated

(c)   Room is either cooled or heated

(d)  Room is neither cooled nor heated

Explanation-(b) In a refrigerator, the heat dissipated in the atmosphere is more than that taken from the cooling chamber, therefore the room is heated if the door of a refrigerator is kept open.