I thinks it’s 2...........
1. The velocity decreases, and the kinetic energy decreases.
2. An increase in temperature difference between the inside and outside of the building.
3. The total kinetic energy remains the same.
4. 76,761 J
5. The energy loss must increase.
If you heat that air by 100 degrees F, it weighs about 7 grams less. Therefore, each cubic foot of air contained in a hot air balloon can lift about 7 grams. That's not much, and this is why hot air balloons are so huge -- to lift 1,000 pounds, you need about 65,000 cubic feet of hot air.
The sound gets louder as it gets closer and when it passes is gets softer
