Problem: Airport:

The majority of the world's airports are non-towered, with no air traffic control presence. Busy airports have air traffic control (ATC) system. All airports use a traffic pattern to assure smooth traffic flow between departing and arriving aircraft. There are a number of aids available to pilots, though not all airports are equipped with them. Many airports have lighting that help guide planes using the runways and taxiways at night or in rain, snow, or fog. In the U.S. and Canada, the vast majority of airports, large and small, will either have some form of automated airport weather station, a human observer or a combination of the two. Air safety is an important concern in the operation of an airport, and airports often have their own safety services.

What is an important concern in the operation of an airport?
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A: Air safety


Problem: Antarctica:

Antarctica (US English i/æntˈɑːrktɪkə/, UK English /ænˈtɑːktɪkə/ or /ænˈtɑːtɪkə/ or /ænˈɑːtɪkə/)[Note 1] is Earth's southernmost continent, containing the geographic South Pole. It is situated in the Antarctic region of the Southern Hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean. At 14,000,000 square kilometres (5,400,000 square miles), it is the fifth-largest continent in area after Asia, Africa, North America, and South America. For comparison, Antarctica is nearly twice the size of Australia. About 98% of Antarctica is covered by ice that averages 1.9 km (1.2 mi; 6,200 ft) in thickness, which extends to all but the northernmost reaches of the Antarctic Peninsula.

What is the earths northernmost continent?
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A: unanswerable


Problem: Philadelphia:

Philadelphia's major science museums include the Franklin Institute, which contains the Benjamin Franklin National Memorial; the Academy of Natural Sciences; the Mütter Museum; and the University of Pennsylvania Museum of Archaeology and Anthropology. History museums include the National Constitution Center, the Atwater Kent Museum of Philadelphia History, the National Museum of American Jewish History, the African American Museum in Philadelphia, the Historical Society of Pennsylvania, the Grand Lodge of Free and Accepted Masons in the state of Pennsylvania and The Masonic Library and Museum of Pennsylvania and Eastern State Penitentiary. Philadelphia is home to the United States' first zoo and hospital, as well as Fairmount Park, one of America's oldest and largest urban parks.

Which city had the nations first zoo?
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A: Philadelphia


Problem: Red:

Rothko also began using the new synthetic pigments, but not always with happy results. In 1962 he donated to Harvard University a series of large murals of the Passion of Christ whose predominant colors were dark pink and deep crimson. He mixed mostly traditional colors to make the pink and crimson; synthetic ultramarine, cerulean blue, and titanium white, but he also used two new organic reds, Naphtol and Lithol. The Naphtol did well, but the Lithol slowly changed color when exposed to light. Within five years the deep pinks and reds had begun to turn light blue, and by 1979 the paintings were ruined and had to be taken down.

What was the result of the change in color in the Rothko Passion of the Christ murals?
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A:
ruined and had to be taken down