Stocks are clawing back some of the ground they lost, adding 900 points, or 4.7%, to the Dow Jones Industrial Average. The gain early Friday got back less than half of the Dow’s losses from a day earlier, which was the worst day for the market since the Black Monday crash of 1987. European markets rose 4% a day after one of their worst drops on record. The wild swings continued as governments stepped up precautions against the spread of the new coronavirus and considered ways to cushion the blow to their economies. Asian markets ended a volatile day mostly lower.