Now Playing: 08-22-13 Marketplace - Trading, interrupted

The tech-heavy trading on the Nasdaq stock exchange was halted by technical glitch. That means investors were unable to exchange the shares of more than 3,000 U.S. companies including Google, Apple and Microsoft. Its the latest problem in a series of mistakes and errors for the U.S. securities trading business. President Obama spoke about college affordability and what his administration is planning to do to lower costs for an education -- but what does a college degree actually cost?