The balloon wall pushes the enosed air particles inwards.
By definition, the mechanical advantage is the relationship that exists between the output force or load lifted and the value of the force applied.
Thus, using the definition, we have that the mechanical advantage is given by:

Therefore, the mechanical advantage of lifting the box by using a pulley is equal to 1.
Answer:
The mechanical advantage in this situation is:
Equal to 1
This column actually appears due to the body parts reflecting the light of the sun or moon to the observer.
If the body is not perfectly smooth, only parts of this body would be at the correct position to reflect the light of the sun or moon to the observer.
If the body was perfectly smooth, it would act like a mirror where you can see the full image of the sun or the moon reflected on it.