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Washington University has a large number of student-run musical groups on campus, including 12 official a cappella groups. The Pikers, an all-male group, is the oldest such group on campus. The Greenleafs, an all-female group is the oldest (and only) female group on campus. The Mosaic Whispers, founded in 1991, is the oldest co-ed group on campus. They have produced 9 albums and have appeared on a number of compilation albums, including Ben Folds' Ben Folds Presents: University A Cappella! The Amateurs, who also appeared on this album, is another co-ed a cappella group on campus, founded in 1991. They have recorded seven albums and toured extensively. After Dark is a co-ed a cappella group founded in 2001. It has released three albums and has won several Contemporary A Capella Recording (CARA) awards. In 2008 the group performed on MSNBC during coverage of the vice presidential debate with specially written songs about Joe Biden and Sarah Palin. The Ghost Lights, founded in 2010, is the campus's newest and only Broadway, Movies, and Television soundtrack group. They have performed multiple philanthropic concerts in the greater St. Louis area and were honored in November 2010 with the opportunity to perform for Nobel Laureate Douglass North at his birthday celebration.
How many albums have The Greenleafs produced?
A: unanswerable

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Professional anthropological bodies often object to the use of anthropology for the benefit of the state. Their codes of ethics or statements may proscribe anthropologists from giving secret briefings. The Association of Social Anthropologists of the UK and Commonwealth (ASA) has called certain scholarship ethically dangerous. The AAA's current 'Statement of Professional Responsibility' clearly states that "in relation with their own government and with host governments ... no secret research, no secret reports or debriefings of any kind should be agreed to or given."
Secret research and reports are things which should never be what?
A: given

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Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own plane and six others at a greater distance of 290.6 pm. The metal is hard and brittle at most temperatures but becomes malleable between 100 and 150 C. Above 210 C, the metal becomes brittle again and can be pulverized by beating. Zinc is a fair conductor of electricity. For a metal, zinc has relatively low melting (419.5 C) and boiling points (907 C). Its melting point is the lowest of all the transition metals aside from mercury and cadmium.
What is the crystalline structure of sync?
A: hexagonal

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BeiDou-1 is an experimental regional navigation system, which consists of four satellites (three working satellites and one backup satellite). The satellites themselves were based on the Chinese DFH-3 geostationary communications satellite and had a launch weight of 1,000 kilograms (2,200 pounds) each.
What were the BeiDou-1 system satellites based on?
A:
the Chinese DFH-3 geostationary communications satellite