2. (12 points) A line segment of charge has a total charge + q and a length L. Point P is a distance z above the mid-point of the line. The marked piece is a distance x from the mid-point, and has infinitesimal length dx. In terms of dx, x, z, 0, L, q and constants, answer the following: (a) Find an expression for the charge dq on the marked segment. (2 pts) (b) Give an expression for sine and cos0 . (2 pts) (c) Write an expression for the magnitude of the infinitesimal z-component dE, due to the marked piece, at point P. (6 pts) (d) Write an integral expression for the net electric field E at point P. (Note: you do not need to evaluate this integral, just set it up correctly.).. (2 pts)