Smithfield hams hang outside the Taste of Smithfield restaurant and gourmet market in Smithfield, Va. Shuanghui International Holdings plans to buy Smithfield Foods, the world's biggest hog producer. Rich-Joseph Facun/Reuters/Landov hide caption

itoggle caption Rich-Joseph Facun/Reuters/Landov

This photo shows a heavily logged concession affiliated with Asia Pulp and Paper, or APP, one of the world's largest papermakers, on the Indonesian island of Sumatra, in 2010. Romeo Gacad/AFP/Getty Images hide caption

itoggle caption Romeo Gacad/AFP/Getty Images

President Obama, with Education Secretary Arne Duncan at his side, calls on Congress on June 21, 2012, to stop interest rates on student loans from doubling. He is going to make that appeal again Friday. Susan Walsh/AP hide caption

itoggle caption Susan Walsh/AP

A construction worker paints walls at the Maryland Proton Treatment Center in Baltimore. Each of the center's five rooms will contain a massive piece of equipment that will rotate around a cancer patient to deliver a special kind of radiation. Jenny Gold/Kaiser Health News hide caption

itoggle caption Jenny Gold/Kaiser Health News