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