Newport News Shipbuilding has formally agreed to Northrop Grumman's $2.6 billion buyout offer, the two companies announced today. The agreement comes after nearly seven months of wrangling between Northrop and General Dynamics. In April, GD offered NNS a deal in which GD would pay $2.1 billion in cash and take on $500 million in NNS debt. The following month, Northrop Grumman offered 75 percent in shares of Northrop Grumman stock and 25 percent in cash, as well as the debt...