WASHINGTON -- Shares of Archer Daniels Midland Co. rallied about 4% before the opening bell as investors applauded the company's financial results for the second quarter ended Dec. 31. Net profit rose to $729 million, or $1.14 a share, from $561 million, or 88 cents, earned during the same period in fiscal 2010. Quarterly sales reached $20.93 billion from the prior year's $15.91 billion. Earnings growth came from the Decatur, Ill.-based company's corn-processing and agricultural-services businesses.