Figure $23-59$ shows, in
cross section, three infinitely
large nonconducting sheets on
which charge is uniformly
spread. The surface charge
densities are $\sigma_{1}=+2.00$
$\mu \mathrm{C} / \mathrm{m}^{2}, \sigma_{2}=+4.00 \mu \mathrm{C} / \mathrm{m}^{2}$
and $\sigma_{3}=-5.00 \mu \mathrm{Cm}^{2},$ and
distance $L=1.50 \mathrm{cm}$ . In unit-
vector notation, what is the net
electric field at point $P ?$