Walker, Halliday & Resnick — Gauss' Law: Problem 47

47 Figure 23-45 shows a cross section through a very large nonconducting slab of thickness $d = 9.40 \text{ mm}$ and uniform volume charge density $\rho = 1.89 \text{ fC/m}^3$. The origin of an $x$ axis is at the slab’s center. What is the magnitude of the slab’s electric field at an $x$ coordinate of (a) $0$, (b) $2.00 \text{ mm}$, (c) $4.70 \text{ mm}$, and (d) $26.0 \text{ mm}$?