An object that does not move has no forces acting on it.
If an object accelerates, there is definitely a resultant force.
The normal reaction force and weight of an object are an example of an action-reaction pair of forces.
An object's inertia changes depending on where it is.
Normal contact force
There is no normal contact force.
1.5 m/s2 to the left
1.5 m/s2 to the right
6 m/s2 to the left
6 m/s2 to the right