Tech stocks led a mixed showing on Wall Street Tuesday as earnings reports and M&A activity dominated the headlines. A 0.5% early gain for the S&P 500 turned into 0.2% loss by the close. The Dow also reversed lower, falling 0.5%, weighed down by sluggish results at DuPont (DD). The Nasdaq traded in a tight range all day, ending with a 0.4% gain. Volume rose slightly from Monday’s levels across the board. The IBD 50 outperformed, rising 0.6%.