please answer q4 and q5 thank you

Two simple charge configurations encountered a lot in electrostatics are the electric dipole and the uniform line charge. Our goal in this exercise is to derive an expression for the electric potential for these configurations, starting with an expression for the electric potential of a point charge. Recall that the electric potential at an arbitrary point P = (x,y,z) from a point charge q located at the origin is given by V(x,'y,z) = M 'sz+y2+zz i. Suppose we shift the charge by a distance +a along the y-axis, so that it is now located at the point (0,11. 0). Modify the expression for V at point P = (x,y,z). ii. To create an electric dipole, well now add a second opposite charge iq at the position (0, a, 0). Again, find the electric potential V at point P. Determine where V = 0. Describe this region and sketch it on the diagram. Ifyou found the region without explicitly solving for V = 0, justify your approach. iii. Now let's work on the infinite line charge. We can start by treating it as an infinite string of identical point charges along the y-axis, spaced by a distance :1. Write an expression for l/ at point P = (x,y.z) for this configuration. iv. Finally, consider an infinite line ofcharge with charge density J. [what are the units of 1?). Again, write an expression for V at point P = (x,y,z). Since this configuration is really a limiting case of part {iii}, your expression should look similar. How is A related to q and a in part {iii}? v. 0n the diagram for part (iv), sketch an equipotential surface (a region of where the electric potential is constant]