The electric field due to an infintely large, charged plane is uniform in magnitude and direction and can be written LaTeX: \vec{E}=\frac{\sigma}{2\epsilon_0}\ hat{E}E → = σ 2 ϵ 0 E ^, where LaTeX: \sigmaσ is the charge per unit area ("surface charge density") and LaTeX: \hat{E}E ^ is always the same direction, perpendicular to the plane. Consider a uniformly charged disk with a radius of 20 cm. If the electric field vector at point P located a small distance above the disk's center has a magnitude of 708 N/C, what is the disk's approximate charge? Give your answer in units of pC.