The force ‘##F’=11.91k C^2//m^2##.

The gives ##F=(k q_1q_2)/r^2## where ‘k’ is the proportionality constant. It is also called as coulomb’s constant as it as derived from .

Proportionality constant ‘k’ is equal to ‘##(1)/(4piepsilon_0)##’

so substituting the given values in above equation of coulomb’s law we get

.##F=(k(44C)(39C))/(12m)^2##

##:.## The force in terms of coulomb’s constant ‘k’ is ##11.9 k (C^2//m^2)~~12k(C^2//m^2)##