Question

For proper ventilation of building, windows must be open near the bottom and top of the walls so as to let pass.

• A. In more air
• B. In hot air near the roof and cool air out near the bottom
• C. Out hot air near the roof
• D. In cool air near the bottom and hot air out of the roof

Answer 1

The correct option is D In cool air near the bottom and hot air out of the roof

Density of hot air is lesser than the density of cold air so, hot air rises up.