Whether it is a conductor or an insulator they both are important and needed in our life, and electric resistivity is how to distinguish between them. In your answer, give the equation/formula based interrelation between the conductor resistance and its resistivity. The equation/formula should also contain the conductor's length and its cross-sectional area.

If you doubled the conductor length, then what happened to its resistivity and resistance?

If a change of either two quantities (resistivity & resistance) occurred, then by how many times the resistivity or/and resistance increased/decreased? Why?

If the change of the two quantities (resistivity & resistance) didn't occur, then, why?