A line of uniform charge density rhol0 extends from z = -L/2 to z = L/2. Obtain an expression for the potential at the point (0, 0, z) (where z > L/2) using the potential-charge formula (i.e., find the potential by integrating over the charge without finding the electric field first). Assume that the reference point is at infinity, and that the potential at the reference point is zero.