Given a language L and two strings x and y, we write xLy to denote that (mark all that apply) xLandyL for all strings z,xzLyzL there is a string z such that xzLyz/L x and y have no separating extension xLyL there is no string z such that xzLyz/L Let L be a language, and let x and y be two strings. We say x and y have a separating extension z if xLandy/LxLy/L there is a string z such that xzLyz/L there is a string z such that xzL and yz/L xL,yL,andz/L