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Article: A new study links heavy air pollution from coal burning to shorter lives in northern China. Researchers estimate that the half-billion people alive there in the 1990s will live an average of 5 years less than their southern counterparts because they breathed dirtier air. China itself made the comparison possible: for decades, a now-discontinued government policy provided free coal for heating, but only in the colder north. Researchers found significant differences in both _ pollution of the air and life expectancy in the two regions. While previous studies have found that pollution affects human health, "the deeper and ultimately more important question is the impact on life expectancy," said one of the researchers, Michael Greenstone, a professor of environmental economics at Massachusetts Institute of Technology. "This study provides a unique setting to answer the life expectancy question because the(heating) policy dramatically changes pollution concentrations ,,,Greenstone said in an email. "Further, due to the low rates of migration in China in this period, we can know people's exposure over long time periods," he said. The policy gave free coal for fuel boilers to heat homes and offices to cities north of the Huai Rivwhich divides China into north and south. It was in effect for much of the 1950-198,0 period of central planning, and, though discontinued after 1980, it has left a legacy in the north of heavy coal burning, which releases particulate pollutants into the air that can harm human health. Researchers found no other government policies that treated China's north differently from the south. The researchers collected data for 90 cities, from 1981 to 2000, on the annual daily average concentration of total suspended particulates. In China, those are considered to be particulates that are 100 micrometers or less in diameter, sent out from sources including power stations, construction sites and vehicles. Among them, PM2.5 is of especially great health concern because it can go deep into the... Question: According to Greenstone, _ greatly contributed to the high pollution concentrations in North China. Yes or no, is the answer "the free heating policy"?
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No

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Article: The First Hello The man from the telephone department got off the bus, and made his way to the tea stall, wiping the sweat off his head, face, then slipping his handkerchief under his shirt to wipe his neck and back. It was a year ago that the phone line had been installed, six months later men from the public works department had come to put up the phone booth -- a neat box-like structure, with a glass window, and wooden ledges, yellow in colour. And days after that, a painter had taken an entire day to colour in broad, black brushstrokes, the words: STD Booth, local and STD allowded. No one could tell that the last word had been misspelled. Besides, he had taken the entire day. After he had a cup of tea, he had left, waving cheerfully. And now months later, someone else was here again. Everyone watched the man as he sat on the bench. No one said a word, and soon the sound of him slurping his tea filled the hot afternoon. A few leaves fell, heavy in the heat, and sometimes a car passed, on its way to the main city farther away. When the man had finished, he made to pay but the tea shop owner who sat behind his steaming kettle and the washed upturned cups, waved him away. "You are our guest here." So the man took his handkerchief out again and wiped his face. They crowded around him as he shut himself up in the phone booth. When the children pressed their nose against the glass, he shooed them away, as he took out a shiny black instrument and placed it on the narrow shelf. A sigh of satisfaction passed through everyone that soon changed to an excited yell as they saw him dial a number, pressing a finger into the ringed dialer of the phone and letting it go all the way in a half-circle. A while later, they hear him say into the mouthpiece, "Hello." "Hello, " the children around the booth took up the cry, the teashop owner broke into a smile and the men waiting for a bus smiled and said hello to each other. The sadhu who sat under the banyan tree nodded wisely. As the sound carried, more hellos were heard.... Question: The examples of the children, the teashop owner, the men waiting for the bus, the women and the shepherds are given to illustrate _ . Yes or no, is the answer "the local people's curiosity for the new thing"?
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Yes

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Article: Searching for airfares often seems like a game that passengers are bound to lose. Prices change from day to day, even minute to minute. Looking through multiple websites for the best deal can be a big challenge. Even when you do book, there's no guarantee that you are going to get the best price. "You just don't know when to _ . It's not like buying anything else I can think of," said George Hobica, founder of Airfarewatchdog.com. Harriet Levy paid $179 for a recent round-trip flight on American Airlines between New York and Fort Lauderdale, Florida. Sitting just one row behind her, Shirley Harrison paid $215. A few rows back, Ellis and Dianne Traub paid $317 each. There were at least 12 fares on the flight, ranging from $169 to $360. There's no reason for it, Harrison said. Fares can fluctuate significantly in just a few hours. One Delta flight from New York to Los Angeles jumped from $755 to $1,143 from a Friday to Saturday in late April, then fell to $718 on Sunday. The flight was one of a dozen the Associated Press followed over three months for a vacation between July 16 and 22. The number one finding: avoid booking tickets on weekends. It's the most expensive time to buy. There's no way to guarantee the best fare. But before booking, travelers should pay attention to this additional advice: * Book on Tuesday, Wednesday and Thursday. That's when airlines most often offer sales. * Buy in advance, but not too early. The best time is four to six weeks before traveling. In general, prices for any given flight are highest eight to 10 weeks and two to three weeks in advance. * Make use of social media. Airlines are giving more benefits like exclusive sales to travelers who interact with them on Twitter and Facebook. Those specials are often gone within hours. * The so-called discount airlines - JetBlue, Air-Tran, Southwest and Frontier - adjust their fares less frequently than other airlines, so you can feel more confident that the price will stay the same. But their prices aren't always the lowest.... Question: By using a lot of figures, the author intends to _ . Yes or no, is the answer "prove airfares can vary widely"?
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No