17. Fix a nonzero complex number zo. Show that the set D obtained from the plane by deleting the ray {tzo: 0 1} (d) D={z=x+iy: x > 0 and [x> y + 1 or x > 1-y]} 20. Show that each star-shaped set is connected. Chapter 1 The Complex Plane Separation of a Point and Convex Set Let C be a closed convex set and zo a point not in C. It is a fact that there is a point p in C with r=zo-pl