Question: The first centrally organised police force was created by the government of King Louis XIV in 1667 to police the city of Paris, then the largest city in Europe. The royal edict, registered by the Parlement of Paris on March 15, 1667 created the office of lieutenant general de police ("lieutenant general of police"), who was to be the head of the new Paris police force, and defined the task of the police as "ensuring the peace and quiet of the public and of private individuals, purging the city of what may cause disturbances, procuring abundance, and having each and everyone live according to their station and their duties".
Is there an answer to this question: What was the smallest European city in 1667?

Answer: unanswerable

Question: In a series of famous papers, von Neumann made spectacular contributions to measure theory. The work of Banach had implied that the problem of measure has a positive solution if n = 1 or n = 2 and a negative solution in all other cases. Von Neumann's work argued that the "problem is essentially group-theoretic in character, and that, in particular, for the solvability of the problem of measure the ordinary algebraic concept of solvability of a group is relevant. Thus, according to von Neumann, it is the change of group that makes a difference, not the change of space."
Is there an answer to this question: What concept was relevant to the solvability of the problem of measure?

Answer: algebraic concept of solvability of a group is relevant

Question: Over a dozen racial categories would be recognized in conformity with all the possible combinations of hair color, hair texture, eye color, and skin color. These types grade into each other like the colors of the spectrum, and not one category stands significantly isolated from the rest. That is, race referred preferentially to appearance, not heredity, and appearance is a poor indication of ancestry, because only a few genes are responsible for someone's skin color and traits: a person who is considered white may have more African ancestry than a person who is considered black, and the reverse can be also true about European ancestry. The complexity of racial classifications in Brazil reflects the extent of miscegenation in Brazilian society, a society that remains highly, but not strictly, stratified along color lines. These socioeconomic factors are also significant to the limits of racial lines, because a minority of pardos, or brown people, are likely to start declaring themselves white or black if socially upward, and being seen as relatively "whiter" as their perceived social status increases (much as in other regions of Latin America).
Is there an answer to this question: What way would categories grade into each other, rather than being isolated from each other?

Answer: like the colors of the spectrum

Question: Following the ceasefire agreement that suspended hostilities (but not officially ended) in the 1991 Gulf War, the United States and its allies instituted and began patrolling Iraqi no-fly zones, to protect Iraq's Kurdish and Shi'a Arab populationboth of which suffered attacks from the Hussein regime before and after the Gulf Warin Iraq's northern and southern regions, respectively. U.S. forces continued in combat zone deployments through November 1995 and launched Operation Desert Fox against Iraq in 1998 after it failed to meet U.S. demands of "unconditional cooperation" in weapons inspections.
Is there an answer to this question: What did Iraq fail to meet in 1995?

Answer:
unanswerable