Gingrich talks to a breakfast crowd during a campaign stop at the Circle Restaurant in Epsom, N.H., on Friday. A new CBS poll of Republican primary voters finds him tied for second place with Mitt Romney, behind Herman Cain.
On July 28, officials sent in the Washington police to evict the marchers. The action was peaceful until someone threw a brick, the police reacted with force, and two bonus marchers were shot. The situation quickly spiraled out of control.
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Power plants that burn fossil fuels release carbon dioxide as well as a complex soup of chemicals, including nitrogen and sulfur. These chemicals in the air actually help keep global warming in check by reflecting sunlight back into space. Above, the Bruce Mansfield Power Plant in Shippingport, Pa.
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