Kayna Whitworth has the latest on the eight feared dead after a B-52 bomber crashed shortly after takeoff outside Los Angeles, according to officials; Rachel Scott reports on the new deal with Iran, exact details haven't been released, with Iran and the US giving conflicting descriptions of what's in the agreement; David Muir reports on the outpouring of support for longtime WABC anchor Bill Ritter after sharing his diagnosis of early-stage Alzheimer’s, and what he’s now saying about his health