The air inside becomes warmer, and that makes it LESS DENSE.
Less-dense air FLOATS in denser air. Since it's inside the balloon, it picks the balloon up when it floats.
Answer:
1. The resistance of any physical object to any velocity
2. It continues in it's existing state of rest or uniform motion
3. Mass is a quantity that is solely dependent upon the inertia of an object.
With its apparent magnitude
1. Resonance. Mechanical waves act on or through a medium, these waves can often have frequencies that are synchronized in a way that makes them act on the matter in the medium more "aggressively."
