Problem: Compact disc:

In 2004, worldwide sales of audio CDs, CD-ROMs and CD-Rs reached about 30 billion discs. By 2007, 200 billion CDs had been sold worldwide. CDs are increasingly being replaced by other forms of digital storage and distribution, with the result that audio CD sales rates in the U.S. have dropped about 50% from their peak; however, they remain one of the primary distribution methods for the music industry. In 2014, revenues from digital music services matched those from physical format sales for the first time.

What percent decrease did audio CD sales experience?
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A: 50%

Problem: Mexico City:

The city's first bus rapid transit line, the Metrobus, began operation in June 2005, along Avenida Insurgentes. Line 2 opened in December 2008, serving Eje 4 Sur, line 3 opened in February 2011, serving Eje 1 Poniente, and line 4 opened in April 2012 connecting the airport with San Lazaro and Buenavista Station at Insurgentes. As the microbuses were removed from its route, it was hoped that the Metrobus could reduce pollution and decrease transit time for passengers. In June 2013, Mexico City's mayor announced two more lines to come: Line 5 serving Eje 3 Oriente and Line 6 serving Eje 5 Norte. As of June 2013, 367 Metrobus buses transported 850,000 passengers daily.

How many people ride the Metrobus every day?
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A: 850,000

Problem: Yale University:

Yale's secret society buildings (some of which are called "tombs") were built both to be private yet unmistakable. A diversity of architectural styles is represented: Berzelius, Donn Barber in an austere cube with classical detailing (erected in 1908 or 1910); Book and Snake, Louis R. Metcalfe in a Greek Ionic style (erected in 1901); Elihu, architect unknown but built in a Colonial style (constructed on an early 17th-century foundation although the building is from the 18th century); Mace and Chain, in a late colonial, early Victorian style (built in 1823). Interior moulding is said to have belonged to Benedict Arnold; Manuscript Society, King Lui-Wu with Dan Kniley responsible for landscaping and Josef Albers for the brickwork intaglio mural. Building constructed in a mid-century modern style; Scroll and Key, Richard Morris Hunt in a Moorish- or Islamic-inspired Beaux-Arts style (erected 186970); Skull and Bones, possibly Alexander Jackson Davis or Henry Austin in an Egypto-Doric style utilizing Brownstone (in 1856 the first wing was completed, in 1903 the second wing, 1911 the Neo-Gothic towers in rear garden were completed); St. Elmo, (former tomb) Kenneth M. Murchison, 1912, designs inspired by Elizabethan manor. Current location, brick colonial; Shabtai, 1882, the Anderson Mansion built in the Second Empire architectural style; and Wolf's Head, Bertram Grosvenor Goodhue (erected 1923-4).

Who was responsible for landscaping the Manuscript Society building?
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A: Dan Kniley

Problem: Nigeria:

In 1885, British claims to a West African sphere of influence received recognition from other European nations at the Berlin Conference. The following year, it chartered the Royal Niger Company under the leadership of Sir George Taubman Goldie. In 1900 the company's territory came under the control of the British government, which moved to consolidate its hold over the area of modern Nigeria. On 1 January 1901, Nigeria became a British protectorate, and part of the British Empire, the foremost world power at the time. In the late 19th and early 20th centuries the independent kingdoms of what would become Nigeria fought a number of conflicts against the British Empire's efforts to expand its territory. By war, the British conquered Benin in 1897, and, in the Anglo-Aro War (19011902), defeated other opponents. The restraint or conquest of these states opened up the Niger area to British rule.

When did the British government take over the Royal Niger Company's territory?
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A:
1900