Stocks opened mixed this morning after a strong runup the previous session that pushed the Dow Jones industrial average to its highest level since the October crash. The widely watched index of 30 industrials was off 0.71 to 2,151.49 by 10 a.m. EDT. Among broader market indicators, the New York Stock Exchange composite index of all listed issues rose 0.01 to 155.36. The American Stock Exchange market-value index fell 0.05 to 308.54. Losing issues narrowly outnumbered declines on the NYSE, with 460 down, 417 up and 547 unchanged. Volume on the Big Board totaled 24.07 million shares after the first 30 minutes. Brokers differed on their short-term outlook for stocks. Some expected prices to weaken from investors selling stocks to capture profits from the market's Wednesday surge. Others said the dollar's strength and eased pressure on interest rates would lure more people into the market and boost prices. On Wednesday, the Dow Jones industrial average rose 43.03 points to 2,152.20, its highest level since the crash eight months ago. Advancing issues outnumbered declines by about an 11-to-4 ratio in nationwide trading of NYSE-listed stocks, with 1,144 up, 413 down and 420 unchanged. Big Board volume totaled 217.51 million shares, up from 155.06 million previously.