Two charged objects attract each other with a force F. What happens to the force between them if one charge is doubled, the other charge is tripled, and the separation distance between their centers is reduced to one-fourth its original value? The force is now equal to

The law of conservation of electric charge: The net amount of electric charge produced in any process is zero. or
No net electric charge can be created or destroyed.

Three properties of conductors in static equilibrium.
1. The electric field inside a conductor is zero in the static situation.
2. Any net charge on a conductor distributes itself on the surface.
3. The electric field is always perpendicular to the surface outside of a conductor.

Gauss's law: The total flux summed over any closed surface is equal to the net charge enclosed by the surface divided by eo.