A point charge causes an electric flux of \( -2 \times 10^{4} \, \text{N m}^{2} \text{C}^{-1} \) to pass through a spherical Gaussian surface of \( 8.0 \, \text{cm} \) radius, centred on the charge. The value of the point charge is:
(Given \( \varepsilon_{0} = 8.85 \times 10^{-12} \, \text{C}^{2} \text{N}^{-1} \text{m}^{-2} \))
