Question

What is the magnitude of the electric force between two muons having equal but opposite charge, separated by 6.4 × 10⁻⁸ m?
a) 5.62 × 10⁻¹⁴ N
b) 6.4 × 10⁻⁸ N
c) 5.62 × 10⁻²⁰ N
d) 6.4 × 10⁻¹⁴ N