An infinite line charge produces an electric field of $9 × 10^6 N/C$ at a distance of 20 cm. The linear charge density will be:

$10^{-3} C/m$ $10^{-4} C/m$ $10^{-2} C/m$ $10^{-5} C/m$

$10^{-4} C/m$

The correct answer is Option (2) → $10^{-4} C/m$