I am trying to export the data in geojson or json format from this rest service I keep getting error request can someone help me with the input querys

http://maps3.arcgisonline.com/ArcGIS/rest/services/A-16/FEMA_100-Year_Flood_Zones_in_the_USA/MapServer/1

I need the geometry and attributes returned

I am using this page to try and query for all of the data http://maps3.arcgisonline.com/ArcGIS/rest/services/A-16/FEMA_100-Year_Flood_Zones_in_the_USA/MapServer/1/query

I choose the format as JSON and in the Return Fields (Comma Separated): I enter "*"

what else do I need to enter into the QUERY to return this layer.

UPDATE

I entered objectid is not null into the where clause and it returned the cryptic ESRI rings format

http://maps3.arcgisonline.com/ArcGIS/rest/services/A-16/FEMA_100-Year_Flood_Zones_in_the_USA/MapServer/1/query?text=&geometry=&geometryType=esriGeometryPoint&inSR=&spatialRel=esriSpatialRelIntersects&relationParam=&objectIds=&where=objectid+is+not+null&time=&returnIdsOnly=false&returnGeometry=true&maxAllowableOffset=&outSR=&outFields=%22*%22&f=pjson