Concept:Hot air rises because it becomes less dense than the cooler air around it.Explanation:The hot metal is suspended at the centre of the box. It heats the surrounding air. This heated air expands, becomes less dense and rises towards the top of the box. The thermometer in contact with the upper side, therefore, receives the hottest air and records the highest temperature. The lower and side thermometers are not affected as much because heat transfer by convection mainly carries heat upward. In the diagram, thermometer E is the one placed on the upper side.Answer:D. E
