Marsh   McLennan to Cut 3,000 Jobs  NEW YORK (Reuters) - Marsh   McLennan Cos. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=MMC.N target=/stocks/quickinfo/fullquote"&gt;MMC.N&lt;/A&gt;, the  insurance broker at the center of a bid-rigging scandal, on  Tuesday said it will lay off 3,000 employees, or 5 percent of  its work force.