This diagram shows the positions of three ornithologists on a map. The squares on the map are 1000m along each side.[image of diagram] The ornithologists are trying to find an injured falcon which is carrying a radio transmitter. Each ornithologist has a radio tracking device. The direction-finding part of the trackers is not working but the signal strength gives an indication of the distance to the bird. The ornithologists have the following information about the distance from themselves to the bird. Gordon is at position 22,06; signal strength indicates more than 500m and less than 2000m. Helen is at position 23,06; signal strength indicates more than 100m and less than 2000m. Ingrid is at position 23,08; signal strength indicates more than 1100m and less than 1800m.