alfred p. sloan foundation, supporting public understanding of science, technology, engineering and mathematics. >> o'brien: passed. there's something that's both scary and awesome about nuclear energy. >> it will you give the rate at which you're receiving radiation as well as how much you've accumulated. >> o'brien: oh, i see. thanks to the magic of nuclear fission, this plant, indian point, generates about a quarter of new york city's electricity with no greenhouse gases or air pollution. but the reality is indian poins nuclear technology is not cutting edge; it's old. >> so this is one of three emergency diesel generators. >> o'brien: the two working reactors here came on line some 40 years ago. it looks like an locomotive engine. westinghouse makes those, so i guess that makes sense. how many of these do you have, first of all? old as the plant is, indian point's owner, entergy, wants to run it for another 20 years. and that makes some people uneasy. after all, this plant is in the most densely populated region in the u.s.-- times square is only about 35 miles away. >> you are 35 miles fro

alfred p. sloan foundation. supporting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> woodruff: for mitt romney, it's a night to celebrate. he scored a resounding victory in florida, sweeping all 50 delegates and regaining the mantle of republican presidential front-runner. with more than three-quarters of the precincts counted, romney had a wide lead over newt gingrich, 47% to 32%. it came just ten days after gingrich had trounced him in south carolina. romney claimed his victory this evening, before supporters at the tampa convention center. >> primary contests are not easy. they're not suppose to be. as this primary unfolds our opponents and other party are watching. they hraoeub to comfort themselves with the fact a competitive campa

alfred p. sloan foundation. supporting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. captioning sponsored by macneil/lehrer productions captioned by media access group at wgbh access.wgbh.org

alfred p. sloan foundation. supporting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. captioning sponsored by macneil/lehrer productions captioned by media access group at wgbh access.wgbh.org >> this is "bbc world news america." funding for this presentation is made possible by the freeman foundation of new york, stowe, vermont, and honolulu. newman's own foundation. and union bank. >> at union bank, our relationship managers work hard to understand the industry you operate in, working to nurture new ventures and help provide capital for key, strategic decisions. we offer expertise and tailored solutions in a wide range of industries. what can we do for you? newsd now, "bbc world america."

alfred p. sloan foundation. upporting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. captioning sponsored by macneil/lehrer productions captioned by media access group at wgbh access.wgbh.org >> this is "bbc world news america." >> funding for this presentation is made possible by -- the freeman foundation of new york, stowe, vermont, and honolulu, newman's own foundation, and union bank. >> at union bank, our relationship managers use their expertise in global finance to guide you through the business strategies and opportunities of international commerce. we put our extended global network to work for a wide range of companies, from small businesses to major corporations. what can we do for you? >> and now "bbc world news america."

alfred p. sloan foundation.porting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> brown: afghanistan was tense with protests and religious fury today. the continuing fallout over the burning of korans by u.s. troops. at least seven people died in clashes with afghan security forces. hundreds of angry afghans streamed to protest sites across the country. they set fires, threw stones and voiced their rage at nato and american forces. >> ( translated ): these occupiers who disrespected the quran many times, in bagram, in guantanamo and in other places, should leave afghanistan. they are doing this to insult islam and muslims. we cannot tolerate this insult. >> woodruff: in some places, the protests turned violent. police said they were fire

alfred p. sloan foundation. supporting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> ifill: this was primary day in arizona and michigan, with 59 republican delegates at stake. mitt romney and rick santorum were the main contenders, and tensions were high, especially in michigan. the romney campaign went into the day struggling to hold off what has turned out to be an aggressive and heated challenge from rick santorum in romney's native state. in the final days before today's open primary, the santorum campaign has staked its claim in michigan even using automated robo-calls to get democratic crossover votes. >> michigan democrats can vote in the republican primary on tuesday. why is it so important? romney's supporting the bailouts for

alfred p. sloan foundation.porting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> ifill: it was a big night and day after for rick santorum. he swept the latest round of republican presidential nominating tests and, in so doing, altered the complexion of the race. >> conservatism is alive and well in missouri and minnesota. >> ifill: the former pennsylvania senator scored decisive victories in both those states, plus a five-point win in colorado out gunning frontrunner mitt romney in all three of tuesday's contests. >> i don't stand here today to claim to be the conservative alternative to mitt romney, i stand here to be the conservative alternative to barack obama. >> ifill: santorum won with minimal turnout-- less than 6% of the voting

alfred p. sloan foundation. supporting science, technology, and improved economic performance and financial literacy in the 21st century. >> and with the ongoing support of these institutions and foundations. and... >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> brown: china's rise offers the u.s. economic opportunities, not threats. that was the message today, as the man expected to be his country's future leader ended his american visit in los angeles, and a prominent u.s. film company announced it would open a studio in china. the new company will be called oriental dreamworks, a joint venture between dreamworks animation and several chinese media groups. dreamworks has enjoyed box office success in china, led by the "kung fu panda" franchise. but china has placed severe restrictions on the distribution of american films in the country. the deal came together as vice president xi jinping wrapped up his

alfred p. sloan foundation. supporting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> woodruff: the republican presidential race in florida came to a close today after a rough-and-tumble ten days. it boiled down to a two-man race, and attacks on the stump and a blitzkrieg of broadcast ads raged on to the very end. at stake: a trove of 50 delegates, and momentum heading into february. republicans predicted a record turnout in florida, more than two million voters. and mitt romney hoped for a decisive victory. >> i'm mitt romney. how are you this morning. >> woodruff: romney started his day greeting volunteers and phoning voters from his headquarters in tampa. the former massachusetts governor's appeal for support won over those like bill