Question

What is the reaction force to the normal force exerted by the table?

Answer 1

Newton's third law states that every action has an equal and opposite reaction force. The object on the table exerts its weight as a force, against the table. However, as Newton's third law states, the table exerts an equal an opposite force, which is called the NORMAL FORCE. In mechanics, the normal force is that component of the contact force that is perpendicular to the surface that an object contacts. Here, the surface of the table  prevents the
 object from falling.