Stocks opened higher in steady trade Thursday. The Nasdaq powered up 0.6% at the open. The S&P 500 added 0.3% and the Dow Jones industrial average put up a 0.3% gain. The stock market today opened with volume up about 2% on both the NYSE and the Nasdaq compared with the same time Wednesday. Leaders were in fervid motion: Tesla Motors (TSLA) dropped 10% and Keurig Green Mountain (GMCR) jumped 6% after reporting quarterly results.