Awwal 02, 1432, April 06, 2011, SPA -- U.S. stocks ended mixed on Tuesday, as investors grew concerned over meeting minutes from the U.S. Federal Reserve (Fed). In world markets, European stocks were also mixed, as the FTSE 100 in London was down 0.1 percent. The Nikkei in Japan ended 1 percent lower, while other Asian markets were closed for a holiday. In U.S. economic news, a report from the Institute for Supply Management (ISM) showed that activity in the service-sector eased slightly last month. The ISM non-manufacturing index fell to 57.3 in March from 59.7 in February. In U.S. company news, stocks were supported by gains in the semiconductor companies after Texas Instruments (TI) announced a $6.5 billion offer for National Semiconductor. Shares of National Semiconductor surged 2 percent. --MORE