Stocks dropped on Wall Street in midday trading Thursday. Markets were unable to hold gains from Wednesday's rally. The Dow Jones Industrial fell more than 200 points. Apple (AAPL) continues to fall. Shares were down for a second straight day and is now trading below $100. Glitches in its iPhones and operating system have investors turning sour on the stock. Attorney General Eric Holder will resign. He's expected to announce his plans to leave the Justice Department later this afternoon. Holder was the country's first African-American attorney general and held that position for nearly six years. Nike (NKE) will report its quarterly earnings after the markets close. Analysts are expecting a positive report from athletic-wear company. Shares of Nike are following the market momentum and trading lower.