Dow gains 21 points, while S&P and Nasdaq also rise. BestBuy stock soars on buyout offer, while Knight Capital loses a quarter of its value, despite $400 million in financing.
The Dow lost 33 points to close at 12598, continuing its rocky performance during the month of May.
US stocks faltered Monday on trouble in China and Greece. The Dow lost 14 points to close at 12962