Problem: Association football:

At a professional level, most matches produce only a few goals. For example, the 200506 season of the English Premier League produced an average of 2.48 goals per match. The Laws of the Game do not specify any player positions other than goalkeeper, but a number of specialised roles have evolved. Broadly, these include three main categories: strikers, or forwards, whose main task is to score goals; defenders, who specialise in preventing their opponents from scoring; and midfielders, who dispossess the opposition and keep possession of the ball to pass it to the forwards on their team. Players in these positions are referred to as outfield players, to distinguish them from the goalkeeper. These positions are further subdivided according to the area of the field in which the player spends most time. For example, there are central defenders, and left and right midfielders. The ten outfield players may be arranged in any combination. The number of players in each position determines the style of the team's play; more forwards and fewer defenders creates a more aggressive and offensive-minded game, while the reverse creates a slower, more defensive style of play. While players typically spend most of the game in a specific position, there are few restrictions on player movement, and players can switch positions at any time. The layout of a team's players is known as a formation. Defining the team's formation and tactics is usually the prerogative of the team's manager.

Who's job is to prevent the opponents from scoring?
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A: defenders

Problem: The Endangered Species Conservation Act (P. L. 91-135), passed in December, 1969, amended the original law to provide additional protection to species in danger of "worldwide extinction" by prohibiting their importation and subsequent sale in the United States. It expanded the Lacey Act's ban on interstate commerce to include mammals, reptiles, amphibians, mollusks and crustaceans. Reptiles were added mainly to reduce the rampant poaching of alligators and crocodiles. This law was the first time that invertebrates were included for protection.
How did the Endangered Species Conservation Act benefit endangered species?
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Answer: by prohibiting their importation and subsequent sale in the United States

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In addition to numerous articles on mathematics, Whitehead wrote three major books on the subject: A Treatise on Universal Algebra (1898), Principia Mathematica (co-written with Bertrand Russell and published in three volumes between 1910 and 1913), and An Introduction to Mathematics (1911). The former two books were aimed exclusively at professional mathematicians, while the latter book was intended for a larger audience, covering the history of mathematics and its philosophical foundations. Principia Mathematica in particular is regarded as one of the most important works in mathematical logic of the 20th century.
When did Whitehead write his first book?
A: 1898

Context and question: In almost all federations the central government enjoys the powers of foreign policy and national defense as exclusive federal powers. Were this not the case a federation would not be a single sovereign state, per the UN definition. Notably, the states of Germany retain the right to act on their own behalf at an international level, a condition originally granted in exchange for the Kingdom of Bavaria's agreement to join the German Empire in 1871. Beyond this the precise division of power varies from one nation to another. The constitutions of Germany and the United States provide that all powers not specifically granted to the federal government are retained by the states. The Constitution of some countries like Canada and India, on the other hand, state that powers not explicitly granted to the provincial governments are retained by the federal government. Much like the US system, the Australian Constitution allocates to the Federal government (the Commonwealth of Australia) the power to make laws about certain specified matters which were considered too difficult for the States to manage, so that the States retain all other areas of responsibility. Under the division of powers of the European Union in the Lisbon Treaty, powers which are not either exclusively of European competence or shared between EU and state as concurrent powers are retained by the constituent states.
In nearly all federalism countries, central powers enjoy what?
Answer: the powers of foreign policy and national defense as exclusive federal powers

Question: Capacity building is an ongoing problem experienced by NPOs for a number of reasons. Most rely on external funding (government funds, grants from charitable foundations, direct donations) to maintain their operations and changes in these sources of revenue may influence the reliability or predictability with which the organization can hire and retain staff, sustain facilities, create programs, or maintain tax-exempt status. For example, a university that sells research to for-profit companies may have tax exemption problems. In addition, unreliable funding, long hours and low pay can result in employee retention problems. During 2009, the US government acknowledged this critical need by the inclusion of the Nonprofit Capacity Building Program in the Serve America Act. Further efforts to quantify the scope of the sector and propose policy solutions for community benefit were included in the Nonprofit Sector and Community Solutions Act, proposed during 2010.
Is there an answer to this question: What are some problems that affect employee retention and volunteers?

Answer: unreliable funding, long hours and low pay

Problem: Post-punk:

Generally, post-punk music is defined as music that emerged from the cultural milieu of punk rock in the late 1970s, although many groups now categorized as post-punk were initially subsumed under the broad umbrella of punk or new wave music, only becoming differentiated as the terms came to signify more narrow styles. Additionally, the accuracy of the term's chronological prefix "post" has been disputed, as various groups commonly labeled post-punk in fact predate the punk rock movement. Reynolds defined the post-punk era as occurring loosely between 1978 and 1984.

Who has defined a period of when the post-punk era was?
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A:
Reynolds