I am having some trouble understanding and solving these questions

53 .. Figure 22-42 shows a portion of an infinitely long, con- centric cable in cross section. The inner conductor has a linear charge density of 6.00 nC/m and the outer conductor has no net charge. (a) Find the electric field for all values of R, where R is the perpendicular distance from the common axis of the cylindrical system. (b) What are the surface charge densities on the inside and the outside surfaces of the outer conductor? A = 6 nC/m 13 cm 9 cm 13 cm R FIGURE 22-42 Problems 53 and 5760 . A charge of -6.00 nC is uniformly distributed on a thin square sheet of nonconducting material of edge length 20.0 cm. (a) What is the surface charge density of the sheet? (b) What are the magnitude and direction of the electric field next to the sheet and proximate to the center of the sheet?Two identical square parallel metal plates each have an area of 500 cm-. They are separated by 1.50 cm. They are both initially uncharged. Now a charge of + 1.50 nC is transferred from the plate on the left to the plate on the right and the charges then establish electrostatic equilibrium. (Neglect edge effects.) (a) What is the electric field between the plates at a distance of 0.25 cm from the plate on the right? (b) What is the electric field between the plates a distance of 1.00 cm from the plate on the left? (c) What is the electric field just to the left of the plate on the left? (d) What is the electric field just to the right of the plate on the right? 's