Problem: Immunology:

In the mid-1950s, Frank Burnet, inspired by a suggestion made by Niels Jerne, formulated the clonal selection theory (CST) of immunity. On the basis of CST, Burnet developed a theory of how an immune response is triggered according to the self/nonself distinction: "self" constituents (constituents of the body) do not trigger destructive immune responses, while "nonself" entities (e.g., pathogens, an allograft) trigger a destructive immune response. The theory was later modified to reflect new discoveries regarding histocompatibility or the complex "two-signal" activation of T cells. The self/nonself theory of immunity and the self/nonself vocabulary have been criticized, but remain very influential.

In CST, what triggers a destructive immune response?
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A: "nonself" entities (e.g., pathogens, an allograft)

Problem: The category of Native American applies to the diverse group of people who lived in North America before European settlement. During the U.S. government's westward expansion, Native Americans were displaced from their land which had been their home for centuries. Instead, they were forced onto reservations which were far smaller and less productive. According to Brest, land belonging to Native Americans was reduced from 138 million acres in 1887 to 52 million acres in 1934. In 1990, the poverty rate for Native Americans was more than triple that of the whites and only 9.4% of Native Americans have completed a bachelor's degree as opposed to 25.2% of whites and 12.2% of African Americans.
Which groups can be categorized as Native Americans?
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Answer: people who lived in North America before European settlement

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The 2000 U.S. Census in the write-in response category had a code listing which standardizes the placement of various write-in responses for automatic placement within the framework of the U.S. Census's enumerated races. Whereas most responses can be distinguished as falling into one of the five enumerated races, there remains some write-in responses which fall into the "Mixture" heading which cannot be racially categorized. These include "Bi Racial, Combination, Everything, Many, Mixed, Multi National, Multiple, Several and Various".
How many race options did the Canadian census have?
A: unanswerable

Context and question: The sensitivity of Earth-based infrared telescopes is significantly limited by water vapor in the atmosphere, which absorbs a portion of the infrared radiation arriving from space outside of selected atmospheric windows. This limitation can be partially alleviated by placing the telescope observatory at a high altitude, or by carrying the telescope aloft with a balloon or an aircraft. Space telescopes do not suffer from this handicap, and so outer space is considered the ideal location for infrared astronomy.
What absorbs infrared radiation from space away from high altitude?
Answer: unanswerable

Question: The term "Late Middle Ages" refers to one of the three periods of the Middle Ages, along with the Early Middle Ages and the High Middle Ages. Leonardo Bruni was the first historian to use tripartite periodization in his History of the Florentine People (1442). Flavio Biondo used a similar framework in Decades of History from the Deterioration of the Roman Empire (14391453). Tripartite periodization became standard after the German historian Christoph Cellarius published Universal History Divided into an Ancient, Medieval, and New Period (1683).
Is there an answer to this question: What 1683 work resulted in the standard use of tripartite periodization?

Answer: Universal History Divided into an Ancient, Medieval, and New Period

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In Suriname today, Dutch is the sole official language, and over 60 percent of the population speaks it as a mother tongue. Dutch is the obligatory medium of instruction in schools in Suriname, even for non-native speakers. A further twenty-four percent of the population speaks Dutch as a second language. Suriname gained its independence from the Netherlands in 1975 and has been an associate member of the Dutch Language Union since 2004. The lingua franca of Suriname, however, is Sranan Tongo, spoken natively by about a fifth of the population.
What's the common language that around 20% of Suriname's people speak?
A:
Sranan Tongo