U.S. stocks fell at open on Friday after President Donald Trump threatened to slap new tariffs on China over the coronavirus crisis, while Apple and Amazon became the latest companies to warn of more pain in the future.
The Dow Jones Industrial Average <.DJI> fell 224.94 points, or 0.92%, at the open to 24,120.78.
The S&P 500 <.SPX> ope
