Summary Companies GE, 3M up on strong full-year profit forecasts Verizon climbs on surprise rise in subscriber additions RTX shares tumble on Pratt & Whitney jet engine problem Indexes: Dow down 0.03%, S&P up 0.13%, Nasdaq up 0.52% July 25 (Reuters) - The tech-heavy Nasdaq and the S&P 500 edged up amid choppy trading on Tuesday as investors geared up for quarterly earnings reports from megacap technology companies Alphabet (GOOGL.O) and Microsoft (MSFT.O), and a rate hike by the Federal Reserve. With the central bank on track for another 25-basis point interest rate hike on Wednesday, policymakers face a choice...