The answer is position 3, because it is at its lowest point.
Potential Energy is “stored energy.” It is energy that is ready to be converted or released as another type of energy. We most often think of potential energy as gravitational potential energy. When objects are higher up, they are ready to fall back down. When you stretch an object and it has a tendency to return to its original shape, it is said to have elastic potential energy. Chemical potential energy is the stored energy in a substance’s chemical structure that can be released in a chemical reaction or as heat.
The more the number of shells will let go of their outer electrons more easily because the effective nuclear charge on the outer (valence) electrons will be lower. This is called 'shielding', the outer electrons will be shielded from the nucleus by the inner electrons.
Particles in a: gas are well separated with no regular arrangement. liquid are close together with no regular arrangement. solid are tightly packed, usually in a regular pattern.