840a7572_ices___Open_Static_Map_Service__Description
[Request Parameter] scale [Example Request Data] A valid scale integer. See Zoom to Scale Mapping for information on scales versus zoom levels. [Required] Yes, if the center parameter is present, the zoom parameter is not present, and no POIs are present [Description] 
Specifies display scale for map image.
MapQuest Platform Web Services : Open Static Map Service
Description