HCA Net Falls, Hurt by Florida Hurricanes  NEW YORK (Reuters) - HCA Inc.&lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=HCA.N target=/stocks/quickinfo/fullquote"&gt;HCA.N&lt;/A&gt;, the largest U.S.  hospital chain, reported on Friday lower third-quarter profit  due to unpaid patient bills and hurricanes that hurt admissions  at the company's hospitals in Florida.