National Football League

The National Football League (NFL) is a professional American football league consisting of 32 teams, divided equally between the National Football Conference (NFC) and the American Football Conference (AFC). The NFL is one of the four major professional sports leagues in North America, and the highest professional level of American football in the world. The NFL's 17-week regular season runs from the week after Labor Day to the week after Christmas, with each team playing sixteen games and having one bye week. Following the conclusion of the regular season, six teams from each conference (four division winners and two wild card teams) advance to the playoffs, a single-elimination tournament culminating in the Super Bowl, played between the champions of the NFC and AFC.

The NFL was formed in 1920 as the American Professional Football Association (APFA) before renaming itself the National Football League for the 1923 season. The NFL agreed to merge with the American Football League (AFL) in 1966, and the first Super Bowl was held at the end of that season; the merger was completed in 1970. Today, the NFL has the highest average attendance (67,591) of any professional sports league in the world and is the most popular sports league in the United States. The Super Bowl is among the biggest club sporting events in the world and individual Super Bowl games account for many of the most watched television programs in American history, all occupying the Nielsen's Top 5 tally of the all-time most watched U.S. television broadcasts by 2015. The NFL's executive officer is the commissioner, who has broad authority in governing the league.

Raven's Progressive Matrices

Raven's Progressive Matrices (often referred to simply as Raven's Matrices) or RPM is a nonverbal group test typically used in educational settings. It is usually a 60 item test used in measuring abstract reasoning and regarded as a non-verbal estimate of fluid intelligence. It is the most common and popular test administered to groups ranging from 5-year-olds to the elderly. It is made of 60 multiple choice questions, listed in order of difficulty. This format is designed to measure the test-taker's reasoning ability, the eductive ("meaning-making") component of Spearman's g. (g is often referred to as general intelligence.) The tests were originally developed by John C. Raven in 1936. In each test item, the subject is asked to identify the missing element that completes a pattern. Many patterns are presented in the form of a 6x6, 4x4, 3x3, or 2x2 matrix, giving the test its name.

Versions

The Matrices are available in three different forms for participants of different ability:

YouTube

YouTube is a video-sharing website headquartered in San Bruno, California, United States. The service was created by three former PayPal employees in February 2005. In November 2006, it was bought by Google for US$1.65 billion. YouTube now operates as one of Google's subsidiaries. The site allows users to upload, view, rate, share and comment on videos, and it makes use of WebM, H.264/MPEG-4 AVC, and Adobe Flash Video technology to display a wide variety of user-generated and corporate media video. Available content includes video clips, TV clips, music videos, movie trailers and other content such as video blogging, short original videos, and educational videos.

Most of the content on YouTube has been uploaded by individuals, but media corporations including CBS, the BBC, Vevo, Hulu, and other organizations offer some of their material via YouTube, as part of the YouTube partnership program. Unregistered users can watch videos, and registered users can upload videos to their channels. Videos considered to contain potentially offensive content are available only to registered users affirming themselves to be at least 18 years old.

Teen Titans

The Teen Titans, also known as the New Teen Titans and the Titans, are a superhero team appearing in American comic books published by DC Comics, often in an eponymous monthly series. As the group's name suggests, its members are teenage superheroes. The theme of teenagers learning to take on adult roles and responsibilities was common throughout the series.

The first appearance of the Teen Titans was in The Brave and the Bold #54 (1964) featuring the team of Robin (Dick Grayson), Kid Flash (Wally West) and Aqualad (Garth), the sidekicks of Justice League members Batman, the Flash and Aquaman respectively. The team made its first appearance under the name of "Teen Titans" in The Brave and the Bold #60, joined by new member Wonder Girl (Donna Troy), Wonder Woman's younger sister. Later, Aqualad left the group and, at various times, Green Arrow's sidekick, Speedy (Roy Harper), Lillith, Hawk, Dove, Guardian, Aquagirl, Gnarrk, and Bumblebee joined the original incarnation of the team.

Universal quantification

In predicate logic, a universal quantification is a type of quantifier, a logical constant which is interpreted as "given any" or "for all". It expresses that a propositional function can be satisfied by every member of a domain of discourse. In other words, it is the predication of a property or relation to every member of the domain. It asserts that a predicate within the scope of a universal quantifier is true of every value of a predicate variable.

It is usually denoted by the turned A (∀) logical operator symbol, which, when used together with a predicate variable, is called a universal quantifier ("∀x", "∀(x)", or sometimes by "(x)" alone). Universal quantification is distinct from existential quantification ("there exists"), which asserts that the property or relation holds only for at least one member of the domain.

Quantification in general is covered in the article on quantification (logic). Symbols are encoded U+2200 ∀ FOR ALL (HTML ∀ · ∀ · as a mathematical symbol).