Problem: Han dynasty:

The waterwheel appeared in Chinese records during the Han. As mentioned by Huan Tan in about 20 AD, they were used to turn gears that lifted iron trip hammers, and were used in pounding, threshing and polishing grain. However, there is no sufficient evidence for the watermill in China until about the 5th century. The Nanyang Commandery Administrator Du Shi (d. 38 AD) created a waterwheel-powered reciprocator that worked the bellows for the smelting of iron. Waterwheels were also used to power chain pumps that lifted water to raised irrigation ditches. The chain pump was first mentioned in China by the philosopher Wang Chong in his 1st-century-AD Balanced Discourse.

What was used to power chain pumps to raise water to irrigation ditches?
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A: Waterwheels


Problem: 2008 Sichuan earthquake:

The New York Times reported that "government officials in Beijing and Sichuan have said they are investigating the collapses. In an acknowledgment of the weakness of building codes in the countryside, the National Development and Reform Commission said on May 27 that it had drafted an amendment to improve construction standards for primary and middle schools in rural areas. Experts are reviewing the draft, the commission said." To limit protests, officials pushed parents to sign a document, which forbade them from holding protests, in exchange of money, but some who refused to sign were threatened. The payment amounts varied from school to school but were approximately the same. In Hanwang, parents were offered a package valued at 8,800 USD in cash and a per-parent pension of nearly 5,600 USD. Furthermore, officials used other methods of silencing: riot police officers broke up protests by parents; the authorities set up cordons around the schools; and officials ordered the Chinese news media to stop reporting on school collapses.

Who did the New York Times report was investigating the school collapses?
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A: government officials


Problem: Oklahoma:

Thirty-nine Native American tribal governments are based in Oklahoma, each holding limited powers within designated areas. While Indian reservations typical in most of the United States are not present in Oklahoma, tribal governments hold land granted during the Indian Territory era, but with limited jurisdiction and no control over state governing bodies such as municipalities and counties. Tribal governments are recognized by the United States as quasi-sovereign entities with executive, judicial, and legislative powers over tribal members and functions, but are subject to the authority of the United States Congress to revoke or withhold certain powers. The tribal governments are required to submit a constitution and any subsequent amendments to the United States Congress for approval.

What powers do tribal governments have?
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A: executive, judicial, and legislative powers over tribal members and functions


Problem: Premier League:

There are 20 clubs in the Premier League. During the course of a season (from August to May) each club plays the others twice (a double round-robin system), once at their home stadium and once at that of their opponents, for a total of 38 games. Teams receive three points for a win and one point for a draw. No points are awarded for a loss. Teams are ranked by total points, then goal difference, and then goals scored. If still equal, teams are deemed to occupy the same position. If there is a tie for the championship, for relegation, or for qualification to other competitions, a play-off match at a neutral venue decides rank. The three lowest placed teams are relegated into the Football League Championship, and the top two teams from the Championship, together with the winner of play-offs involving the third to sixth placed Championship clubs, are promoted in their place.

How is a tie for the championship handled?
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A:
If there is a tie for the championship, for relegation, or for qualification to other competitions, a play-off match at a neutral venue decides rank.