US STOCKS-Wall St tumbles 1 pct on oil's drop, Alcoa's revenue By: Reuters: Company News April 12, 2011 at 11:44 AM EDT * Japan raises nuclear crisis level to same as Chernobyl Read More >> Related Stocks: Alcoa Chevron Corp Freeport-McMoRan Hewlett-Packard Rio Tinto Plc ADR S&P Metals & Mining SPDR Standard & Poors 500