1. The problem statement, all variables and given/known data How do you find the electric fields of regions between parallel infinite sheets of charge? The set up: 3 parallel infinite sheets of charge a,b,c from left to right. Region 1 is to the left sheet a. Region 2 is between sheets a and b. Region 3 is between sheets b and c. Region 4 is to the right of sheet c. They only give you the surface charge densities of each sheet. Each surface charge density is different. How do I go about finding the electric field E in regions 1,2,3 and 4? 2. Relevant equations I know the electric field of an infinite charged plane is E= η/ 2ε_0, but don't know what to do. 3. The attempt at a solution Lost. I tried adding the electric fields together, but that doesn't give me the correct answer. Edit: I now have the solution.