If the complex number z is imagined as a point in the complex plane, then its conjugate z is the point obtained from z by reflecting in the real axis. What are the complex numbers obtained from z by the following geometric transformations?
(a) 180orotation about 0.
(b) Reflection in the imaginary axis.
(c) 45oclockwise rotation about 0.
(d) Reflection in the line y = x.