Closing Bell Exchange: Nasdaq halts trading

To discuss Nasdaq's impact on the markets is Ann Miletti, Wells Fargo Advantage Funds; Ron Muhlenkamp; Brian Stutland, Stutland Volatility Group; Ben Willis, Albert Fried & Company; and CNBC's Rick Santelli, Bob Pisani, Bertha Coombs, Kate Kelly, and Dominic Chu.