Stocks opened mostly higher Friday, but saw the Nasdaq Composite dragged down by a plunge for shares of social-media platform Snap Inc. The Dow Jones Industrial Average DJIA, +0.33% rose 124 points, or 0.4%, to 32,160, while the S&P 500 SPX, +0.09% traded near unchanged after opening with a small gain. The Nasdaq Composite COMP, -0.41% shed 0.4%, while Snap shares dropped 34% in early activity, dragged down after the company reported disappointing results after Thursday’s closing bell.