C is the third letter in the English alphabet and a letter of the alphabets of many other writing systems which inherited it from the Latin alphabet. It is also the third letter of the ISO basic Latin alphabet. It is named cee (pronounced /siː/) in English.
|Writing system||Latin script|
|Language of origin||Latin language|
Numerical value: 3
|Old Latin |
"C" comes from the same letter as "G". The Semites named it gimel. The sign is possibly adapted from an Egyptian hieroglyph for a staff sling, which may have been the meaning of the name gimel. Another possibility is that it depicted a camel, the Semitic name for which was gamal. Barry B. Powell, a specialist in the history of writing, states "It is hard to imagine how gimel = "camel" can be derived from the picture of a camel (it may show his hump, or his head and neck!)".
In the Etruscan language, plosive consonants had no contrastive voicing, so the Greek 'Γ' (Gamma) was adopted into the Etruscan alphabet to represent /k/. Already in the Western Greek alphabet, Gamma first took a '' form in Early Etruscan, then '' in Classical Etruscan. In Latin it eventually took the 'c' form in Classical Latin. In the earliest Latin inscriptions, the letters 'c k q' were used to represent the sounds /k/ and /ɡ/ (which were not differentiated in writing). Of these, 'q' was used to represent /k/ or /ɡ/ before a rounded vowel, 'k' before 'a', and 'c' elsewhere. During the 3rd century BC, a modified character was introduced for /ɡ/, and 'c' itself was retained for /k/. The use of 'c' (and its variant 'g') replaced most usages of 'k' and 'q'. Hence, in the classical period and after, 'g' was treated as the equivalent of Greek gamma, and 'c' as the equivalent of kappa; this shows in the romanization of Greek words, as in 'ΚΑΔΜΟΣ', 'ΚΥΡΟΣ', and 'ΦΩΚΙΣ' came into Latin as 'cadmvs', 'cyrvs' and 'phocis', respectively.
Other alphabets have letters homoglyphic to 'c' but not analogous in use and derivation, like the Cyrillic letter Es (С, с) which derives from the lunate sigma, named due to its resemblance to the crescent moon.
When the Roman alphabet was introduced into Britain, ⟨c⟩ represented only /k/, and this value of the letter has been retained in loanwords to all the insular Celtic languages: in Welsh, Irish, Gaelic, ⟨c⟩ represents only /k/. The Old English Latin-based writing system was learned from the Celts, apparently of Ireland; hence ⟨c⟩ in Old English also originally represented /k/; the Modern English words kin, break, broken, thick, and seek, all come from Old English words written with ⟨c⟩: cyn, brecan, brocen, þicc, and séoc. But during the course of the Old English period, /k/ before front vowels (/e/ and /i/) were palatalized, having changed by the tenth century to [tʃ], though ⟨c⟩ was still used, as in cir(i)ce, wrecc(e)a. On the continent, meanwhile, a similar phonetic change had also been going on (for example, in Italian).
In Vulgar Latin, /k/ became palatalized to [tʃ] in Italy and Dalmatia; in France and the Iberian peninsula, it became [ts]. Yet for these new sounds ⟨c⟩ was still used before the letters ⟨e⟩ and ⟨i⟩. The letter thus represented two distinct values. Subsequently, the Latin phoneme /kʷ/ (spelled ⟨qv⟩) de-labialized to /k/ meaning that the various Romance languages had /k/ before front vowels. In addition, Norman used the letter ⟨k⟩ so that the sound /k/ could be represented by either ⟨k⟩ or ⟨c⟩, the latter of which could represent either /k/ or /ts/ depending on whether it preceded a front vowel letter or not. The convention of using both ⟨c⟩ and ⟨k⟩ was applied to the writing of English after the Norman Conquest, causing a considerable re-spelling of the Old English words. Thus while Old English candel, clif, corn, crop, cú, remained unchanged, Cent, cæ´ᵹ (cé´ᵹ), cyng, brece, séoce, were now (without any change of sound) spelled 'Kent', 'keȝ', 'kyng', 'breke', and 'seoke'; even cniht ('knight') was subsequently changed to 'kniht' and þic ('thick') changed to 'thik' or 'thikk'. The Old English 'cw' was also at length displaced by the French 'qu' so that the Old English cwén ('queen') and cwic ('quick') became Middle English 'quen' 'quik', respectively. The sound [tʃ], to which Old English palatalized /k/ had advanced, also occurred in French, chiefly from Latin /k/ before 'a'. In French it was represented by the digraph ⟨ch⟩, as in champ (from Latin camp-um) and this spelling was introduced into English: the Hatton Gospels, written about 1160, have in Matt. i-iii, child, chyld, riche, mychel, for the cild, rice, mycel, of the Old English version whence they were copied. In these cases, the Old English ⟨c⟩ gave place to ⟨k qu ch⟩ but, on the other hand, ⟨c⟩ in its new value of /ts/ came in largely in French words like processiun, emperice, grace, and was also substituted for 'ts' in a few Old English words, as miltse, bletsien, in early Middle English milce, blecien. By the end of the thirteenth century both in France and England, this sound /ts/ de-affricated to /s/; and from that time ⟨c⟩ has represented /s/ before front vowels either for etymological reasons, as in lance, cent, or to avoid the ambiguity due to the "etymological" use of ⟨s⟩ for /z/, as in ace, mice, once, pence, defence.
Thus, to show etymology, English spelling has advise, devise (instead of advize, devize), while advice, device, dice, ice, mice, twice, etc., do not reflect etymology; example has extended this to hence, pence, defence, etc., where there is no etymological reason for using ⟨c⟩. Former generations also wrote sence for sense. Hence, today the Romance languages and English have a common feature inherited from Vulgar Latin spelling conventions where ⟨c⟩ takes on either a "hard" or "soft" value depending on the following letter.
In English orthography, ⟨c⟩ generally represents the "soft" value of /s/ before the letters ⟨e⟩ (including the Latin-derived digraphs ⟨ae⟩ and ⟨oe⟩, or the corresponding ligatures ⟨æ⟩ and ⟨œ⟩), ⟨i⟩, and ⟨y⟩, and a "hard" value of /k/ before any other letters or at the end of a word. However, there are a number of exceptions in English: "soccer" and "Celt" are words that have /k/ where /s/ would be expected.
The "soft" ⟨c⟩ may represent the /ʃ/ sound in the digraph ⟨ci⟩ when this precedes a vowel, as in the words 'delicious' and 'appreciate', and also in the word "ocean" and its derivatives.
The digraph ⟨ch⟩ most commonly represents /tʃ/, but can also represent /k/ (mainly in words of Greek origin) or /ʃ/ (mainly in words of French origin). For some dialects of English, it may also represent /x/ in words like loch, while other speakers pronounce the final sound as /k/. The trigraph ⟨tch⟩ always represents /tʃ/.
The digraph ⟨ck⟩ is often used to represent the sound /k/ after short vowels.
In the Romance languages French, Spanish, Italian, Romanian and Portuguese, ⟨c⟩ generally has a "hard" value of /k/ and a "soft" value whose pronunciation varies by language. In French, Portuguese, Catalan and Spanish from Latin America and southern Spain, the soft ⟨c⟩ value is /s/ as it is in English. In the Spanish spoken in northern and central Spain, the soft ⟨c⟩ is a voiceless dental fricative /θ/. In Italian and Romanian, the soft ⟨c⟩ is [t͡ʃ].
All Balto-Slavic languages that use the Latin alphabet, as well as Albanian, Hungarian, Pashto, several Sami languages, Esperanto, Ido, Interlingua, and Americanist phonetic notation (and those aboriginal languages of North America whose practical orthography derives from it) use ⟨c⟩ to represent /t͡s/, the voiceless alveolar or voiceless dental sibilant affricate. In romanized Mandarin Chinese, the letter represents an aspirated version of this sound, /t͡sʰ/.
Among non-European languages that have adopted the Latin alphabet, ⟨c⟩ represents a variety of sounds. Yup'ik, Indonesian, Malay, and a number of African languages such as Hausa, Fula, and Manding share the soft Italian value of /t͡ʃ/. In Azeri, Crimean Tatar, Kurmanji Kurdish, and Turkish ⟨c⟩ stands for the voiced counterpart of this sound, the voiced postalveolar affricate /d͡ʒ/. In Yabem and similar languages, such as Bukawa, ⟨c⟩ stands for a glottal stop /ʔ/. Xhosa and Zulu use this letter to represent the click /ǀ/. In some other African languages, such as Beninese Yoruba, ⟨c⟩ is used for /ʃ/. In Fijian, ⟨c⟩ stands for a voiced dental fricative /ð/, while in Somali it has the value of /ʕ/.
As a phonetic symbol, lowercase ⟨c⟩ is the International Phonetic Alphabet (IPA) and X-SAMPA symbol for the voiceless palatal plosive, and capital ⟨C⟩ is the X-SAMPA symbol for the voiceless palatal fricative.
As in English, ⟨ck⟩, with the value /k/, is often used after short vowels in other Germanic languages such as German and Swedish (but some other Germanic languages use ⟨kk⟩ instead, such as Dutch and Norwegian). The digraph ⟨cz⟩ is found in Polish and ⟨cs⟩ in Hungarian, both representing /t͡ʃ/. The digraph ⟨sc⟩ represents /ʃ/ in Old English, Italian, and a few languages related to Italian (where this only happens before front vowels, while otherwise it represents /sk/). The trigraph ⟨sch⟩ represents /ʃ/ in German.
Add to C with diacritics
|Unicode name||LATIN CAPITAL LETTER C||LATIN SMALL LETTER C|
|Numeric character reference||C||C||c||c|
|NATO phonetic||Morse code|
|Signal flag||Flag semaphore||American manual alphabet (ASL fingerspelling)||Braille |
Sir Arthur Charles Clarke (16 December 1917 – 19 March 2008) was a British science fiction writer, science writer and futurist, inventor, undersea explorer, and television series host.
He is famous for being co-writer of the screenplay for the 1968 film 2001: A Space Odyssey, widely considered to be one of the most influential films of all time. Clarke was a science writer, who was both an avid populariser of space travel and a futurist of uncanny ability. On these subjects he wrote over a dozen books and many essays, which appeared in various popular magazines. In 1961 he was awarded the Kalinga Prize, an award which is given by UNESCO for popularising science. These along with his science fiction writings eventually earned him the moniker "Prophet of the Space Age". His other science fiction writings earned him a number of Hugo and Nebula awards, which along with a large readership made him one of the towering figures of science fiction. For many years Clarke, Robert Heinlein and Isaac Asimov were known as the "Big Three" of science fiction.Clarke was a lifelong proponent of space travel. In 1934, while still a teenager, he joined the British Interplanetary Society. In 1945, he proposed a satellite communication system using geostationary orbits. He was the chairman of the British Interplanetary Society from 1946–47 and again in 1951–53.Clarke emigrated from England to Sri Lanka (formerly Ceylon) in 1956, largely to pursue his interest in scuba diving. That year he discovered the underwater ruins of the ancient Koneswaram temple in Trincomalee. Clarke augmented his fame later on in the 1980s, from being the host of several television shows such as Arthur C. Clarke's Mysterious World. He lived in Sri Lanka until his death.Clarke was appointed Commander of the Order of the British Empire (CBE) in 1989 "for services to British cultural interests in Sri Lanka". He was knighted in 1998 and was awarded Sri Lanka's highest civil honour, Sri Lankabhimanya, in 2005.Boeing C-17 Globemaster III
The Boeing C-17 Globemaster III is a large military transport aircraft. It was developed for the United States Air Force (USAF) from the 1980s to the early 1990s by McDonnell Douglas. The C-17 carries forward the name of two previous piston-engined military cargo aircraft, the Douglas C-74 Globemaster and the Douglas C-124 Globemaster II. The C-17 commonly performs tactical and strategic airlift missions, transporting troops and cargo throughout the world; additional roles include medical evacuation and airdrop duties. It was designed to replace the Lockheed C-141 Starlifter, and also fulfill some of the duties of the Lockheed C-5 Galaxy, freeing the C-5 fleet for outsize cargo.Boeing, which merged with McDonnell Douglas in 1997, continued to manufacture C-17s for export customers following the end of deliveries to the U.S. Air Force. Aside from the United States, the C-17 is in service with the United Kingdom, Australia, Canada, Qatar, United Arab Emirates, NATO Heavy Airlift Wing, India, and Kuwait. The final C-17 was completed at the Long Beach, California plant and flown on 29 November 2015.C
C is the third letter in the English alphabet and a letter of the alphabets of many other writing systems which inherited it from the Latin alphabet. It is also the third letter of the ISO basic Latin alphabet. It is named cee (pronounced ) in English.C. S. Lewis
Clive Staples Lewis (29 November 1898 – 22 November 1963) was a British writer and lay theologian. He held academic positions in English literature at both Oxford University (Magdalen College, 1925–1954) and Cambridge University (Magdalene College, 1954–1963). He is best known for his works of fiction, especially The Screwtape Letters, The Chronicles of Narnia, and The Space Trilogy, and for his non-fiction Christian apologetics, such as Mere Christianity, Miracles, and The Problem of Pain.
Lewis and fellow novelist J. R. R. Tolkien were close friends. They both served on the English faculty at Oxford University and were active in the informal Oxford literary group known as the Inklings. According to Lewis's memoir Surprised by Joy, he was baptised in the Church of Ireland, but fell away from his faith during adolescence. Lewis returned to Anglicanism at the age of 32, owing to the influence of Tolkien and other friends, and he became an "ordinary layman of the Church of England". Lewis's faith profoundly affected his work, and his wartime radio broadcasts on the subject of Christianity brought him wide acclaim.
Lewis wrote more than 30 books which have been translated into more than 30 languages and have sold millions of copies. The books that make up The Chronicles of Narnia have sold the most and have been popularised on stage, TV, radio, and cinema. His philosophical writings are widely cited by Christian apologists from many denominations.
In 1956, Lewis married American writer Joy Davidman; she died of cancer four years later at the age of 45. Lewis died on 22 November 1963 from renal failure, one week before his 65th birthday. In 2013, on the 50th anniversary of his death, Lewis was honoured with a memorial in Poets' Corner in Westminster Abbey.C (programming language)
C (, as in the letter c) is a general-purpose, imperative computer programming language, supporting structured programming, lexical variable scope and recursion, while a static type system prevents many unintended operations. By design, C provides constructs that map efficiently to typical machine instructions, and it has therefore found lasting use in applications that were previously coded in assembly language. Such applications include operating systems, as well as various application software for computers ranging from supercomputers to embedded systems.
C was originally developed at Bell Labs by Dennis Ritchie, between 1972 and 1973. It was created to make utilities running on Unix. Later, it was applied to re-implementing the kernel of the Unix operating system. During the 1980s, C gradually gained popularity. Nowadays, it is one of the most widely used programming languages, with C compilers from various vendors available for the majority of existing computer architectures and operating systems. C has been standardized by the American National Standards Institute (ANSI) since 1989 (see ANSI C) and subsequently by the International Organization for Standardization (ISO).
C is an imperative procedural language. It was designed to be compiled using a relatively straightforward compiler, to provide low-level access to memory, to provide language constructs that map efficiently to machine instructions, and to require minimal runtime support. Despite its low-level capabilities, the language was designed to encourage cross-platform programming. A standards-compliant C program that is written with portability in mind can be compiled for a wide variety of computer platforms and operating systems with few changes to its source code; the language has become available on various platforms, from embedded microcontrollers to supercomputers.C Sharp (programming language)
C# (pronounced C sharp) is a general-purpose, multi-paradigm programming language encompassing strong typing, lexically scoped, imperative, declarative, functional, generic, object-oriented (class-based), and component-oriented programming disciplines. It was developed around 2000 by Microsoft within its .NET initiative and later approved as a standard by Ecma (ECMA-334) and ISO (ISO/IEC 23270:2018). C# is one of the programming languages designed for the Common Language Infrastructure.
C# was designed by Anders Hejlsberg, and its development team is currently led by Mads Torgersen. The most recent version is C# 7.3, which was released in 2018 alongside Visual Studio 2017 version 15.7.2.Celsius
The Celsius scale, also known as the centigrade scale, is a temperature scale used by the International System of Units (SI). As an SI derived unit, it is used by all countries except the United States, the Bahamas, Belize, the Cayman Islands and Liberia. It is named after the Swedish astronomer Anders Celsius (1701–1744), who developed a similar temperature scale. The degree Celsius (symbol: °C) can refer to a specific temperature on the Celsius scale or a unit to indicate a difference between two temperatures or an uncertainty. Before being renamed to honor Anders Celsius in 1948, the unit was called centigrade, from the Latin centum, which means 100, and gradus, which means steps.
From 1743, the Celsius scale is based on 0 °C for the freezing point of water and 100 °C for the boiling point of water at 1 atm pressure. Prior to 1743, the scale was also based on the boiling and melting points of water, but the values were reversed (i.e. the boiling point was at 0 degrees and the melting point was at 100 degrees). The 1743 scale reversal was proposed by Jean-Pierre Christin.
By international agreement, since 1954 the unit degree Celsius and the Celsius scale are defined by absolute zero and the triple point of Vienna Standard Mean Ocean Water (VSMOW), a specially purified water. This definition also precisely relates the Celsius scale to the Kelvin scale, which defines the SI base unit of thermodynamic temperature with symbol K. Absolute zero, the lowest temperature possible, is defined as being exactly 0 K and −273.15 °C. The temperature of the triple point of water is defined as exactly 273.16 K (0.01 °C). This means that a temperature difference of one degree Celsius and that of one kelvin are exactly the same.On 20 May 2019, the kelvin, and along with it the degree Celsius, will be redefined so that its value will be determined by definition of the Boltzmann constant.Circumference
In geometry, the circumference (from Latin circumferens, meaning "carrying around") of a circle is the (linear) distance around it. That is, the circumference would be the length of the circle if it were opened up and straightened out to a line segment. Since a circle is the edge (boundary) of a disk, circumference is a special case of perimeter. The perimeter is the length around any closed figure and is the term used for most figures excepting the circle and some circular-like figures such as ellipses.
Informally, "circumference" may also refer to the edge itself rather than to the length of the edge.Douglas C-47 Skytrain
The Douglas C-47 Skytrain or Dakota (RAF designation) is a military transport aircraft developed from the civilian Douglas DC-3 airliner. It was used extensively by the Allies during World War II and remains in front line service with various military operators.Halley's Comet
Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 75–76 years. Halley last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061.Halley's returns to the inner Solar System have been observed and recorded by astronomers since at least 240 BC. Clear records of the comet's appearances were made by Chinese, Babylonian, and medieval European chroniclers, but were not recognized as reappearances of the same object at the time. The comet's periodicity was first determined in 1705 by English astronomer Edmond Halley, after whom it is now named.
During its 1986 apparition, Halley's Comet became the first comet to be observed in detail by spacecraft, providing the first observational data on the structure of a comet nucleus and the mechanism of coma and tail formation. These observations supported a number of longstanding hypotheses about comet construction, particularly Fred Whipple's "dirty snowball" model, which correctly predicted that Halley would be composed of a mixture of volatile ices—such as water, carbon dioxide, and ammonia—and dust. The missions also provided data that substantially reformed and reconfigured these ideas; for instance, it is now understood that the surface of Halley is largely composed of dusty, non-volatile materials, and that only a small portion of it is icy.Hepatitis C
Hepatitis C is an infectious disease caused by the hepatitis C virus (HCV) that primarily affects the liver. During the initial infection people often have mild or no symptoms. Occasionally a fever, dark urine, abdominal pain, and yellow tinged skin occurs. The virus persists in the liver in about 75% to 85% of those initially infected. Early on chronic infection typically has no symptoms. Over many years however, it often leads to liver disease and occasionally cirrhosis. In some cases, those with cirrhosis will develop serious complications such as liver failure, liver cancer, or dilated blood vessels in the esophagus and stomach.HCV is spread primarily by blood-to-blood contact associated with intravenous drug use, poorly sterilized medical equipment, needlestick injuries in healthcare, and transfusions. Using blood screening, the risk from a transfusion is less than one per two million. It may also be spread from an infected mother to her baby during birth. It is not spread by superficial contact. It is one of five known hepatitis viruses: A, B, C, D, and E. Diagnosis is by blood testing to look for either antibodies to the virus or its RNA. Testing is recommended in all people who are at risk.There is no vaccine against hepatitis C. Prevention includes harm reduction efforts among people who use intravenous drugs and testing donated blood. Chronic infection can be cured about 95% of the time with antiviral medications such as sofosbuvir or simeprevir. Peginterferon and ribavirin were earlier generation treatments that had a cure rate of less than 50% and greater side effects. Getting access to the newer treatments however can be expensive. Those who develop cirrhosis or liver cancer may require a liver transplant. Hepatitis C is the leading reason for liver transplantation, though the virus usually recurs after transplantation.An estimated 143 million people (2%) worldwide are infected with hepatitis C as of 2015. In 2013 about 11 million new cases occurred. It occurs most commonly in Africa and Central and East Asia. About 167,000 deaths due to liver cancer and 326,000 deaths due to cirrhosis occurred in 2015 due to hepatitis C. The existence of hepatitis C – originally identifiable only as a type of non-A non-B hepatitis – was suggested in the 1970s and proven in 1989. Hepatitis C infects only humans and chimpanzees.Huddersfield Town A.F.C.
Huddersfield Town Association Football Club is a professional football club in Huddersfield, West Yorkshire, England, which competes in the Premier League, the top tier of English football.
Huddersfield became the first English club to win three successive English League titles in 1926, a feat which only three other clubs have matched. The first two league titles were won under legendary manager and pioneer Herbert Chapman, who also led the club to an FA Cup win in 1922. In the late 1950s the club was managed by Bill Shankly and featured Denis Law and Ray Wilson. Following relegation from the First Division in 1972, Huddersfield spent 45 years in the second, third and fourth tiers of English football, before returning to the top flight in 2017.Latin alphabet
The Latin or Roman alphabet is the writing system originally used by the ancient Romans to write the Latin language.Lockheed C-130 Hercules
The Lockheed C-130 Hercules is an American four-engine turboprop military transport aircraft designed and built originally by Lockheed (now Lockheed Martin). Capable of using unprepared runways for takeoffs and landings, the C-130 was originally designed as a troop, medevac, and cargo transport aircraft. The versatile airframe has found uses in a variety of other roles, including as a gunship (AC-130), for airborne assault, search and rescue, scientific research support, weather reconnaissance, aerial refueling, maritime patrol, and aerial firefighting. It is now the main tactical airlifter for many military forces worldwide. More than 40 variants of the Hercules, including civilian versions marketed as the Lockheed L-100, operate in more than 60 nations.
The C-130 entered service with the U.S. in 1956, followed by Australia and many other nations. During its years of service, the Hercules family has participated in numerous military, civilian and humanitarian aid operations. In 2007, the C-130 became the fifth aircraft to mark 50 years of continuous service with its original primary customer, which for the C-130 is the United States Air Force. The C-130 Hercules is the longest continuously produced military aircraft at over 60 years, with the updated Lockheed Martin C-130J Super Hercules currently being produced.Louis C.K.
Louis Székely () (born September 12, 1967), better known by his stage name Louis C.K. (), is an American-Mexican stand-up comedian, writer, actor, and filmmaker. In 2012, C.K. won a Peabody Award and has received six Primetime Emmy Awards, as well as numerous awards for The Chris Rock Show, Louie, and his stand-up specials Live at the Beacon Theater (2011) and Oh My God (2013). He has won the Grammy Award for Best Comedy Album twice. Rolling Stone ranked C.K.'s stand-up special Shameless number three on their "Divine Comedy: 25 Best Stand-Up Specials and Movies of All Time" list and ranked him fourth on its 2017 list of the 50 best stand-up comics of all time.C.K. began his career in the 1990s writing for comedians including David Letterman, Conan O'Brien, Dana Carvey, Chris Rock, and also for other comedy shows. He was also directing surreal short films and went on to direct two features—Tomorrow Night (1998) and Pootie Tang (2001).
In 2001, C.K. released his debut comedy album, Live in Houston, directly through his website and became among the first performers to offer direct-to-fan sales of tickets to his stand-up shows, as well as DRM-free video concert downloads, via his website. He has released nine comedy albums, often directing and editing his specials as well.
He had supporting acting roles in the films American Hustle, Blue Jasmine (both 2013), and Trumbo (2015). C.K. created, directed, executive produced, starred in, wrote, and was the primary editor of Louie, an acclaimed semi-autobiographical comedy-drama series aired from 2010 to 2015 on FX. In 2016, C.K. created and starred in his self-funded web series Horace and Pete. He also co-created the shows Baskets and Better Things for FX and voiced the protagonist Max in the animated film The Secret Life of Pets in the same year. His 2017 film, I Love You, Daddy, was pulled from distribution prior to its scheduled release date after he was accused of past sexual misconduct, to which he admitted.Radiocarbon dating
Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon.
The method was developed in the late 1940s by Willard Libby, who received the Nobel Prize in Chemistry for his work in 1960. It is based on the fact that radiocarbon (14C) is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen. The resulting 14C combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire 14C by eating the plants. When the animal or plant dies, it stops exchanging carbon with its environment, and from that point onwards the amount of 14C it contains begins to decrease as the 14C undergoes radioactive decay. Measuring the amount of 14C in a sample from a dead plant or animal such as a piece of wood or a fragment of bone provides information that can be used to calculate when the animal or plant died. The older a sample is, the less 14C there is to be detected, and because the half-life of 14C (the period of time after which half of a given sample will have decayed) is about 5,730 years, the oldest dates that can be reliably measured by this process date to around 50,000 years ago, although special preparation methods occasionally permit accurate analysis of older samples.
Research has been ongoing since the 1960s to determine what the proportion of 14C in the atmosphere has been over the past fifty thousand years. The resulting data, in the form of a calibration curve, is now used to convert a given measurement of radiocarbon in a sample into an estimate of the sample's calendar age. Other corrections must be made to account for the proportion of 14C in different types of organisms (fractionation), and the varying levels of 14C throughout the biosphere (reservoir effects). Additional complications come from the burning of fossil fuels such as coal and oil, and from the above-ground nuclear tests done in the 1950s and 1960s. Because the time it takes to convert biological materials to fossil fuels is substantially longer than the time it takes for its 14C to decay below detectable levels, fossil fuels contain almost no 14C, and as a result there was a noticeable drop in the proportion of 14C in the atmosphere beginning in the late 19th century. Conversely, nuclear testing increased the amount of 14C in the atmosphere, which attained a maximum in about 1965 of almost twice what it had been before the testing began.
Measurement of radiocarbon was originally done by beta-counting devices, which counted the amount of beta radiation emitted by decaying 14C atoms in a sample. More recently, accelerator mass spectrometry has become the method of choice; it counts all the 14C atoms in the sample and not just the few that happen to decay during the measurements; it can therefore be used with much smaller samples (as small as individual plant seeds), and gives results much more quickly. The development of radiocarbon dating has had a profound impact on archaeology. In addition to permitting more accurate dating within archaeological sites than previous methods, it allows comparison of dates of events across great distances. Histories of archaeology often refer to its impact as the "radiocarbon revolution". Radiocarbon dating has allowed key transitions in prehistory to be dated, such as the end of the last ice age, and the beginning of the Neolithic and Bronze Age in different regions.S.S.C. Napoli
Società Sportiva Calcio Napoli, commonly referred to as Napoli (pronounced [ˈnaːpoli]), is an Italian professional football club based in Naples, Campania that plays in Serie A, the top flight of Italian football. The club have won two league titles, five Coppa Italias, two Supercoppa Italiana titles, and one UEFA Cup.Formed in 1926, the club saw relatively little success in its early years, winning one Coppa Italia until 1965, where they were refounded. Napoli then saw increased success in the 1980s, after the club acquired Diego Maradona. During his time in Naples, Maradona helped the team win several trophies, which led to the club retiring his number 10 jersey. Following his departure, however, Napoli struggled financially, and endured several relegations, prior to being refounded in 2004 by film producer Aurelio De Laurentiis. Under his guise, the club has stabilized, which has led to renewed on-field success.
By attendance, Napoli have the fourth biggest fanbase in Italy, and were ranked as the fifth highest-earning football club in Serie A, with $182 million in revenue during the 2017–18 season. In 2018, Forbes estimated the club is the fifth most valuable club in Italy, worth $379 million. Napoli are also one of the associate members of the European Club Association.
Since 1959, the club has played their home games at Stadio San Paolo, and have traditionally worn sky blue shirts and white shorts. The club also have a long-standing rivalry with Roma, with whom they contest the Derby del Sole. The club's anthem is "'O surdato 'nnammurato".Triangle
A triangle is a polygon with three edges and three vertices. It is one of the basic shapes in geometry. A triangle with vertices A, B, and C is denoted .
In Euclidean geometry any three points, when non-collinear, determine a unique triangle and simultaneously, a unique plane (i.e. a two-dimensional Euclidean space). In other words, there is only one plane that contains that triangle, and every triangle is contained in some plane. If the entire geometry is only the Euclidean plane, there is only one plane and all triangles are contained in it; however, in higher-dimensional Euclidean spaces, this is no longer true. This article is about triangles in Euclidean geometry, and in particular, the Euclidean plane, except where otherwise noted.Vitamin C
Vitamin C, also known as ascorbic acid and L-ascorbic acid, is a vitamin found in various foods and sold as a dietary supplement. It is used to prevent and treat scurvy. Vitamin C is an essential nutrient involved in the repair of tissue and the enzymatic production of certain neurotransmitters. It is required for the functioning of several enzymes and is important for immune system function. It also functions as an antioxidant.Current evidence does not support its use for the prevention of the common cold. There is, however, some evidence that regular use may shorten the length of colds. It is unclear whether supplementation affects the risk of cancer, cardiovascular disease, or dementia. It may be taken by mouth or by injection.Vitamin C is generally well tolerated. Large doses may cause gastrointestinal discomfort, headache, trouble sleeping, and flushing of the skin. Normal doses are safe during pregnancy. The United States Institute of Medicine recommends against taking large doses.Vitamin C was discovered in 1912, isolated in 1928, and in 1933 was the first vitamin to be chemically produced. It is on the World Health Organization Model List of Essential Medicines, which lists the most effective and safe medicines needed in a health system. Vitamin C is available as an inexpensive generic and over-the-counter medication. Partly for its discovery, Albert Szent-Györgyi and Walter Norman Haworth were awarded the 1937 Nobel Prizes in Physiology and Medicine and Chemistry, respectively. Foods containing vitamin C include citrus fruits, kiwifruit, broccoli, Brussels sprouts, raw bell peppers, and strawberries. Prolonged storage or cooking may reduce vitamin C content in foods.Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington or D.C., is the capital of the United States. Founded after the American Revolution as the seat of government of the newly independent country, Washington was named after George Washington, first President of the United States and Founding Father. As the seat of the United States federal government and several international organizations, Washington is an important world political capital. The city is also one of the most visited cities in the world, with more than 20 million tourists annually.The signing of the Residence Act on July 16, 1790, approved the creation of a capital district located along the Potomac River on the country's East Coast. The U.S. Constitution provided for a federal district under the exclusive jurisdiction of the U.S. Congress, and the District is therefore not a part of any state. The states of Maryland and Virginia each donated land to form the federal district, which included the pre-existing settlements of Georgetown and Alexandria. The City of Washington was founded in 1791 to serve as the new national capital. In 1846, Congress returned the land originally ceded by Virginia; in 1871, it created a single municipal government for the remaining portion of the District.
Washington had an estimated population of 702,455 as of July 2018, making it the 20th most populous city in the United States. Commuters from the surrounding Maryland and Virginia suburbs raise the city's daytime population to more than one million during the workweek. Washington's metropolitan area, the country's sixth largest, had a 2017 estimated population of 6.2 million residents.All three branches of the U.S. federal government are centered in the District: Congress (legislative), president (executive), and the U.S. Supreme Court (judicial). Washington is home to many national monuments, and museums, primarily situated on or around the National Mall. The city hosts 177 foreign embassies as well as the headquarters of many international organizations, trade unions, non-profits, lobbying groups, and professional associations, including the World Bank Group, the International Monetary Fund (IMF), the Organization of American States, AARP, the National Geographic Society, the Human Rights Campaign, the International Finance Corporation, and the American Red Cross.
A locally elected mayor and a 13‑member council have governed the District since 1973. However, Congress maintains supreme authority over the city and may overturn local laws. D.C. residents elect a non-voting, at-large congressional delegate to the House of Representatives, but the District has no representation in the Senate. The District receives three electoral votes in presidential elections as permitted by the Twenty-third Amendment to the United States Constitution, ratified in 1961.
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