With the presidential election just a few months away, President Trump and Democratic hopeful former vice president Joe Biden are returning to the campaign trail. How are they making their case to lead a nation in crises? Also, Amazon is putting a one-year moratorium on police use of its facial-recognition technology, yielding to pressure from police-reform advocates and civil rights groups. And, a U.S. grad student imprisoned in Iran for more than three years tells his story for the first time since being released in December.