Also

AIRLINES

* UAL Corp. asked the federal government for a $1.6-billion loan guarantee to help raise $2 billion for United Airlines’ exit from bankruptcy protection.

* Tenet Healthcare Corp. said it planned to close one of its Philadelphia hospitals by the end of March.

* Berkshire Hathaway Inc. Vice Chairman Charles Munger, chairman of Pasadena-based Wesco Financial Corp., sold 300 shares of the company’s stock for about $24.8 million this week, according to regulatory filings.