Question: Jared Diamond describes an "Evil Quartet" of habitat destruction, overkill, introduced species, and secondary extinctions. Edward O. Wilson prefers the acronym HIPPO, standing for Habitat destruction, Invasive species, Pollution, human over-Population, and Over-harvesting. The most authoritative classification in use today is IUCN's Classification of Direct Threats which has been adopted by major international conservation organizations such as the US Nature Conservancy, the World Wildlife Fund, Conservation International, and BirdLife International.
Is there an answer to this question: Who describes the "IUCN"?

Answer: unanswerable

Question: Chengdu Economic and Technological Development Zone (Chinese: ; pinyin: Chengdu jingji jishu kaifa qu) was approved as state-level development zone in February 2000. The zone now has a developed area of 10.25 km2 (3.96 sq mi) and has a planned area of 26 km2 (10 sq mi). Chengdu Economic and Technological Development Zone (CETDZ) lies 13.6 km (8.5 mi) east of Chengdu, the capital city of Sichuan Province and the hub of transportation and communication in southwest China. The zone has attracted investors and developers from more than 20 countries to carry out their projects there. Industries encouraged in the zone include mechanical, electronic, new building materials, medicine and food processing.
Is there an answer to this question: What is the capital city of Sichuan?

Answer: Chengdu

Question: Another approach to brain function is to examine the consequences of damage to specific brain areas. Even though it is protected by the skull and meninges, surrounded by cerebrospinal fluid, and isolated from the bloodstream by the bloodbrain barrier, the delicate nature of the brain makes it vulnerable to numerous diseases and several types of damage. In humans, the effects of strokes and other types of brain damage have been a key source of information about brain function. Because there is no ability to experimentally control the nature of the damage, however, this information is often difficult to interpret. In animal studies, most commonly involving rats, it is possible to use electrodes or locally injected chemicals to produce precise patterns of damage and then examine the consequences for behavior.
Is there an answer to this question: The brain is separated from the bloodstream by what feature?

Answer: the bloodbrain barrier

Question: While there is some dispute as to the matter of influence, Popper had a long-standing and close friendship with economist Friedrich Hayek, who was also brought to the London School of Economics from Vienna. Each found support and similarities in the other's work, citing each other often, though not without qualification. In a letter to Hayek in 1944, Popper stated, "I think I have learnt more from you than from any other living thinker, except perhaps Alfred Tarski." Popper dedicated his Conjectures and Refutations to Hayek. For his part, Hayek dedicated a collection of papers, Studies in Philosophy, Politics, and Economics, to Popper, and in 1982 said, "...ever since his Logik der Forschung first came out in 1934, I have been a complete adherent to his general theory of methodology."
Is there an answer to this question: Who did Alfred Tarski say he had learned more from than any other living thinker?

Answer:
unanswerable