DANBURY—A mobile exhibit honoring first responders of the September 11, 2001 terror attacks will be in the Danbury Fair Mall’s parking lot Monday. The “9/11 Never Forget Mobile Exhibit,” presented by the Stephen Siller Tunnel to Towers Foundation, will be in the mall’s front parking lot from 10 a.m. to 6 p.m. The free-of-charge, 1,000-square-foot exhibit will feature artifacts from the World Trade Center and a depiction of the history of the Twin Towers.