U.S. stocks were mixed on Tuesday while European shares snapped a three-day rally and oil slipped on fear central banks may not deliver enough stimulus this week to quell concerns about a global slowdown. Equities and oil had been climbing steadily since European Central Bank President Mario Draghi said he would do whatever it took to save the euro. Markets interpreted that to mean the ECB could announce at its Thursday meeting plans to lower Spanish and Italian borrowing costs by buying those countries' bonds. Signs of flagging growth in the United States had also raised hopes the Federal Reserve, which begins a ... (full story)