heavy Nasdaq composite index rose 7.12, or 0.3 percent, to 2,112.44. Shares of Amazon.com jumped after brokerages upgraded the online retailer's stock. The New York Stock Exchange composite index rose 8.15 to 6,958.29. The American Stock Exchange composite index rose 1.43 to 1,788.75. And the Russell 2000 index fell 0.80 to 580.35.