Algebra-2

Question Analysis
This problem assesses the understanding of combined variation, specifically the relationship where a quantity (force) varies directly with the product of two other quantities (charges) and inversely with the square of another quantity (distance).

Key Concept Explanation
The relationship can be expressed as , where is a constant.

Step-by-step Solution
1. Given: N, C, C, and m.
2. Substitute these values into the equation to find : .
3. Simplify: or