Answer:
The new force is 1/4 of the previous force.
Step-by-step explanation:
Given
----

---

Required
Determine the new force
Let the two particles be q1 and q2.
The initial force F1 is:
--- Coulomb's law
Substitute 2 for r1


The new force (F2) is

Substitute 4 for r2



Substitute



The new force is 1/4 of the previous force.