By Jennifer Yousfi Managing Editor The U.S. Federal Reserve faces a tough challenge as it kicks off a two-day policymaking meeting tomorrow (Tuesday): It probably needs to start raising interest rates to prop up the U.S. dollar and offset a major escalation in inflationary pressures; but the economy needs low interest rates if it’s to maintain its anemic growth rate. After one of the Fed’s most aggressive rate-cutting campaigns ever slashed short-term interest rates from 5.25% in mid-September to 2.0% now, experts now expect the central bank to reverse course. And this week’s two-day meeting of the policymaking Federal Open Market Committee (FOMC) represents the first chance for the central bank to boost its benchmark Federal Funds rate. Recent hawkish comments by central bank Chairman Ben S. Bernanke had led some analysts to expect a 25-basis point rate increase at this meeting, but ...