Question

Find the value of the point charge with an electric field of 12 N/C and a distance 3.3 m

Answer 1

The Coulomb's law says

$$E=k\frac{q}{r^2}$$

Hence, the charge

$$q=Er^2/k\\ =12*3.3^2/9*10^9=1.5*10^{-8}\:\rm C$$