ASHINGTON, Feb. 12 (Dow Jones/AP) — Air America Radio, the liberal news and talk radio network, has won bankruptcy court approval to sell its assets at an auction Friday, starting with a $4.25 million bid from a consortium of purchasers formed by Stephen L. Green, the chairman of SL Green Realty of New York. Judge Robert D. Drain of Federal Bankruptcy Court in Manhattan said on Friday that the consortium could receive a $150,000 breakup fee if its offer was topped at the auction. Competing bids, which must start at $4.6 million, are due by Thursday with a 10 percent...