(See attachment for diagram and background of this question concerning Gauss' Law)
(a) What is the electric field inside the middle sheet?
(b) What is the electric field between the left and middle sheets?
(c) What is the electric field between the middle and right sheets?
(e) What is the charge density on the surface of the middle sheet facing the right sheet?
The solution gives brief, to the point answers on how to find electric field between three large sheets, mostly with clear explanation, in accordance to Gauss' Law.