Problem: United States Air Force:

During the board process an officer's record is reviewed by a selection board at the Air Force Personnel Center at Randolph Air Force Base in San Antonio, Texas. At the 10 to 11 year mark, captains will take part in a selection board to major. If not selected, they will meet a follow-on board to determine if they will be allowed to remain in the Air Force. Promotion from major to lieutenant colonel is similar and occurs approximately between the thirteen year (for officers who were promoted to major early "below the zone") and the fifteen year mark, where a certain percentage of majors will be selected below zone (i.e., "early"), in zone (i.e., "on time") or above zone (i.e., "late") for promotion to lieutenant colonel. This process will repeat at the 16 year mark (for officers previously promoted early to major and lieutenant colonel) to the 21 year mark for promotion to full colonel.

When does promotion from major to lieutenant colonel in the USAF typically occur?
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A: thirteen year


Problem: Sichuan:

According to the Sichuan Department of Commerce, the province's total foreign trade was US$22.04 billion in 2008, with an annual increase of 53.3 percent. Exports were US$13.1 billion, an annual increase of 52.3 percent, while imports were US$8.93 billion, an annual increase of 54.7 percent. These achievements were accomplished because of significant changes in China's foreign trade policy, acceleration of the yuan's appreciation, increase of commercial incentives and increase in production costs. The 18 cities and counties witnessed a steady rate of increase. Chengdu, Suining, Nanchong, Dazhou, Ya'an, Abazhou, and Liangshan all saw an increase of more than 40 percent while Leshan, Neijiang, Luzhou, Meishan, Ziyang, and Yibin saw an increase of more than 20 percent. Foreign trade in Zigong, Panzhihua, Guang'an, Bazhong and Ganzi remained constant.

What was equal to 13.1 billion CNY?
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A: unanswerable


Problem: Paris:

Paris today has more than 421 municipal parks and gardens, covering more than 3,000 hectares and containing more than 250,000 trees. Two of Paris' oldest and most famous gardens are the Tuileries Garden, created in 1564 for the Tuileries Palace, and redone by André Le Nôtre between 1664 and 1672, and the Luxembourg Garden, for the Luxembourg Palace, built for Marie de' Medici in 1612, which today houses the French Senate. The Jardin des Plantes was the first botanical garden in Paris, created in 1626 by Louis XIII's doctor Guy de La Brosse for the cultivation of medicinal plants.

Who was the Luxembourg palace built for?
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A: Marie de' Medici


Problem: Paper:

The density of paper ranges from 250 kg/m3 (16 lb/cu ft) for tissue paper to 1,500 kg/m3 (94 lb/cu ft) for some speciality paper. Printing paper is about 800 kg/m3 (50 lb/cu ft).

What is the common density of printing paper?
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A:
800 kg/m3