Stocks Boosted by Oil's Fall; Techs Rally  NEW YORK (Reuters) - U.S. blue chips recovered ground on  Friday as falling oil prices offset a profit warning from  aluminum maker Alcoa Inc.  &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=AA.N target=/stocks/quickinfo/fullquote"&gt;AA.N&lt;/A&gt;, while a tech rally was  fueled by software maker Oracle Corp. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=ORCL.O target=/stocks/quickinfo/fullquote"&gt;ORCL.O&lt;/A&gt;