A force is a push or a pull. Under the right circumstances, anything can exert a force.

Push a notebook or some other object so that it slides across a table or desktop. What force causes the notebook to start moving? What force causes the notebook to stop moving?

Explanation:

the force that you applied caused the notebook to move.

the force applied on the notebook by the table causes it to stop moving.

this is because after sometime the book uses up the force and later the force you applied is less than that of the force by the table.

r = ρ x length / area  

ρ = r x area / length  

ρ is in ohm-meters  

in basic units, it is m³kg/s³a²  

i think this is it.