Problem: Sumer:

In the early Sumerian Uruk period, the primitive pictograms suggest that sheep, goats, cattle, and pigs were domesticated. They used oxen as their primary beasts of burden and donkeys or equids as their primary transport animal and "woollen clothing as well as rugs were made from the wool or hair of the animals. ... By the side of the house was an enclosed garden planted with trees and other plants; wheat and probably other cereals were sown in the fields, and the shaduf was already employed for the purpose of irrigation. Plants were also grown in pots or vases."

What animals were domesticated following the Uruk period?
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A: unanswerable


Problem: Glass:

Glass has the ability to refract, reflect, and transmit light following geometrical optics, without scattering it. It is used in the manufacture of lenses and windows. Common glass has a refraction index around 1.5. This may be modified by adding low-density materials such as boron, which lowers the index of refraction (see crown glass), or increased (to as much as 1.8) with high-density materials such as (classically) lead oxide (see flint glass and lead glass), or in modern uses, less toxic oxides of zirconium, titanium, or barium. These high-index glasses (inaccurately known as "crystal" when used in glass vessels) cause more chromatic dispersion of light, and are prized for their diamond-like optical properties.

What can be used to make glass less refractive?
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A: boron


Problem: Uranium:

It is estimated that 5.5 million tonnes of uranium exists in ore reserves that are economically viable at US$59 per lb of uranium, while 35 million tonnes are classed as mineral resources (reasonable prospects for eventual economic extraction). Prices went from about $10/lb in May 2003 to $138/lb in July 2007. This has caused a big increase in spending on exploration, with US$200 million being spent worldwide in 2005, a 54% increase on the previous year. This trend continued through 2006, when expenditure on exploration rocketed to over $774 million, an increase of over 250% compared to 2004. The OECD Nuclear Energy Agency said exploration figures for 2007 would likely match those for 2006.

How much economically viable uranium is there in ore reserves, in billions of tonnes?
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A: unanswerable


Problem: Immunology:

In addition, this Introductory Course gives students more information to complement general biology or science training. It also has two different parts: Part I is an introduction to the basic principles of immunology and Part II is a clinically-oriented lecture series. On the other hand, the Advanced Course is another course for those who are willing to expand or update their understanding of immunology. It is advised for students who want to attend the Advanced Course to have a background of the principles of immunology. Most schools require students to take electives in other to complete their degrees. A Master’s degree requires two years of study following the attainment of a bachelor's degree. For a doctoral programme it is required to take two additional years of study.

What pre-requisite should enrollees in the advanced immunology course have?
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A:
a background of the principles of immunology