Problem: Railway electrification system:

Three-phase AC railway electrification was used in Italy, Switzerland and the United States in the early twentieth century. Italy was the major user, for lines in the mountainous regions of northern Italy from 1901 until 1976. The first lines were the Burgdorf-Thun line in Switzerland (1899), and the lines of the Ferrovia Alta Valtellina from Colico to Chiavenna and Tirano in Italy, which were electrified in 1901 and 1902. Other lines where the three-phase system were used were the Simplon Tunnel in Switzerland from 1906 to 1930, and the Cascade Tunnel of the Great Northern Railway in the United States from 1909 to 1927.

Where did Italy start using the AC system?
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A: in the mountainous regions of northern Italy


Problem: Serbo-Croatian:

South Slavic historically formed a dialect continuum, i.e. each dialect has some similarities with the neighboring one, and differences grow with distance. However, migrations from the 16th to 18th centuries resulting from the spread of Ottoman Empire on the Balkans have caused large-scale population displacement that broke the dialect continuum into many geographical pockets. Migrations in the 20th century, primarily caused by urbanization and wars, also contributed to the reduction of dialectal differences.

What are two characteristics of urbanization?
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A: unanswerable


Problem: John Kerry:

Kerry was arrested on May 30, 1971, during a VVAW march to honor American POWs held captive by North Vietnam. The march was planned as a multi-day event from Concord to Boston, and while in Lexington, participants tried to camp on the village green. At 2:30 a.m., local and state police arrested 441 demonstrators, including Kerry, for trespassing. All were given the Miranda Warning and were hauled away on school buses to spend the night at the Lexington Public Works Garage. Kerry and the other protesters later paid a $5 fine, and were released. The mass arrests caused a community backlash and ended up giving positive coverage to the VVAW.

At what time was Kerry arrested?
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A: 2:30 a.m.


Problem: Diarrhea:

About 1.7 to 5 billion cases of diarrhea occur per year. It is most common in developing countries, where young children get diarrhea on average three times a year. Total deaths from diarrhea are estimated at 1.26 million in 2013 – down from 2.58 million in 1990. In 2012, it is the second most common cause of deaths in children younger than five (0.76 million or 11%). Frequent episodes of diarrhea are also a common cause of malnutrition and the most common cause in those younger than five years of age. Other long term problems that can result include stunted growth and poor intellectual development.

How often do kids get diarrhea in developing countries?
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A:
average three times a year