Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Q: Context: 4-Day Classic Beijing Tour The 4-day classic Beijing tour is designed for tourists who come to visit China for the first time. It covers the most popular and typical places in Beijing, fully displaying the scenery, culture, history, local lifestyles and features, food and drinks, business, etc. for you. Day 1:Arrival in Beijing Your guide meets you at Capital Airport, and helps you check in at your hotel. Enjoy Beijing Duck as welcome dinner. Accommodation: Beijing downtown Day 2:The Great Wall & the Summer Palace Start your day at the most famous part of the Great Wall, the Badaling Great Wall. Leave the downtown for the Great Wall at 8 am. Since it is a long drive to the Great Wall (about 2 hours' riding) have a break at the Jade Museum on the way. Lunch will be enjoyed in a local restaurant. In the early afternoon come back to the city and have a sightseeing tour of the Summer Palace. Recommended Activity: Beijing Opera Show (Liyuan Theatre, 19:30-21: 10 every evening) Accommodation: Beijing downtown Day 3:Beijing city sightseeing & Local experience Your guide meets you at the hotel at 8 am and set out for the day's touring: Tian'anmen Square and the Forbidden City. After visiting the two sites, have a break and get ready for lunch. Hutong visit: see some traditional arts of the old Beijing, such as paper cutting and kite making, and visit a local family. Accommodation: Beijing downtown Day 4:Beijing Olympic sites Visit the Olympic sites: Bird's Nest, Water Cube and Olympic Park, witnessing the fast developing modern China. Enjoy some free time after visiting the sites. After lunch, it is shopping time and then the tour is over. 
 Question: What does this tour company think can show Beijing is a fast developing modern city?

A: bird's nest, water cube and olympic park.
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Q: Context: Vegard Skjerve (born 22 May 1988) is a Norwegian footballer who plays as a defender for Haugesund. 
 Question: What was Vegard Skjerve specialty in their profesisonal sport?

A: defender
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Q: Context: The major cause of outdoor air pollution is the burning of fossil fuels. Fossil fuels are burned in power plants, factories, motor vehicles, and home heating systems. Ranching and using chemicals such as fertilizers also cause outdoor air pollution. Erosion of soil in farm fields, mining activities, and construction sites adds dust particles to the air as well. Some specific outdoor air pollutants are described in Table 25.1. Air Pollutant Sulfur oxides Nitrogen oxides Carbon monoxide Carbon dioxide Particles (dust, smoke) Mercury Smog Ground-level ozone Source coal burning motor vehicle exhaust motor vehicle exhaust all fossil fuel burning wood and coal burning coal burning coal burning motor vehicle exhaust Problem acid rain acid rain poisoning global climate change respiratory problems nerve poisoning respiratory problems respiratory problems Outdoor air pollution causes serious human health problems. For example, pollutants in the air are major contributors to respiratory and cardiovascular diseases. Air pollution may trigger asthma attacks and heart attacks in people with underlying health problems. In fact, more people die each year from air pollution than automobile accidents. Air pollution may also cause acid rain. This is rain that is more acidic (has a lower pH) than normal rain. Acids form in the atmosphere when nitrogen and sulfur oxides mix with water in air. Nitrogen and sulfur oxides come mainly from motor vehicle exhaust and coal burning. If acid rain falls into lakes, it lowers the pH of the water and may kill aquatic organisms. If it falls on the ground, it may damage soil and soil organisms. If it falls on plants, it may make them sick or even kill them. Acid rain also damages stone buildings, bridges, and statues, like the one in Figure 25.1. Another major problem caused by air pollution is global climate change. Gases such as carbon dioxide from the burning of fossil fuels increase the greenhouse effect and raise Earths temperature. The greenhouse effect is a natural feature of Earths atmosphere. It occurs when certain gases in the atmosphere, including carbon dioxide, radiate the suns heat back down to Earths surface. Figure 25.2 shows how this happens. Without greenhouse gases in the atmosphere, the heat would escape into space. The natural greenhouse effect of Earths atmosphere keeps the planets temperature within a range that can support life. The rise in greenhouse gases due to human actions is too much of a good thing. It increases the greenhouse effect and causes Earths average temperature to rise. Rising global temperatures, in turn, are melting polar ice caps and glaciers. Figure 25.3 shows how much smaller the Arctic ice cap was in 2012 than it was in 1984. With more liquid water on Earths surface, sea levels are rising. Adding more heat energy to Earths atmosphere also causes more extreme weather and changes in precipitation patterns. Global warming is already causing food and water shortages and species extinctions. These problems will only grow worse unless steps are taken to curb greenhouse gases and global climate change. You may be able to avoid some of the health effects of outdoor air pollution by staying indoors on high-pollution days. However, some indoor air is just as polluted as outdoor air. One source of indoor air pollution is radon gas. Radon is a radioactive gas that may seep into buildings from rocks underground. Exposure to radon gas may cause lung cancer. Another potential poison in indoor air is carbon monoxide. It may be released by faulty or poorly vented furnaces or other fuel-burning appliances. Indoor furniture, carpets, and paints may release toxic compounds into the air as well. Other possible sources of indoor air pollution include dust, mold, and pet dander. Its easier to control the quality of indoor air than outdoor air. Steps home owners can take to improve indoor air quality include: keeping the home clean so it is as free as possible from dust, mold, and pet dander. choosing indoor furniture, flooring, and paints that are low in toxic compounds such as VOCs (volatile organic compounds). making sure that fuel-burning appliances are working correctly and venting properly. installing carbon monoxide alarms like the one in Figure 25.4 at every level of the home. 
 Question: Exposure to radon gas may cause cancer of the

A:
lung.
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