1 2 3 1 _ _ _ 2 _ _ _ 3 _ _ _ ACROSS 1) the smallest whole number or a numeral representing this number 2) a sign of assent or salutation or command 3) a highly unstable radioactive element (the heaviest of the halogen series); a decay product of uranium and thorium DOWN 1) mother of the ancient irish gods; sometimes identified with danu 2) a sheath worn to protect a finger 3) a rapid automatic system to detect plastic explosives in passengers' luggage using x-ray technology and computers; designed for use in airports ** Scroll down for solution. ** Are you sure you want to peek? ace nod ats