Agriculture commodity trader Archer-Daniels-Midland (ADM -21.25%) placed its chief financial officer on leave as part of an internal investigation into accounting practices. Investors are understandably concerned, sending shares of ADM down nearly 20% as of 10:30 ET Monday. The government has some questions about the books ADM is not typically in the spotlight. But the Chicago-based human and animal nutrition company is on investor radars for all the wrong reasons following a Sunday announcement that it had ...