(1 point) determine whether the given set is open, connected, and simply connected. for example, if it is open, connected, but not simply connected, type "yyn" standing for "yes, yes, no." a. {(x, y)|x> 1,y< 2} yyy b. {(x, y)|2x2+y2< 1} yyy c. {(x, y)|x2−y2< 1} nyy d. {(x, y)|x2−y2> 1} e. {(x, y)|1