The Northrop Grumman B-2 Spirit, also known as the Stealth Bomber, is an American heavy strategic bomber, featuring low-observable stealth technology designed to penetrate dense anti-aircraft defenses. A subsonic flying wing with a crew of two, the plane was designed by Northrop and produced from 1987 to 2000. The bomber can drop conventional and thermonuclear weapons, such as up to eighty 500-pound class (230 kg) Mk 82 JDAM GPS-guided bombs, or sixteen 2,400-pound (1,100 kg) B83 nuclear bombs. The B-2 is the only acknowledged in-service aircraft that can carry large air-to-surface standoff weapons in a stealth configuration.
In mathematics, the Fibonacci sequence is a sequence in which each number is the sum of the two preceding ones. Numbers that are part of the Fibonacci sequence are known as Fibonacci numbers, commonly denoted Fn . The sequence commonly starts from 0 and 1, although some authors start the sequence from 1 and 1 or sometimes from 1 and 2. Starting from 0 and 1, the sequence begins
In statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable. The general form of its probability density function is
Oxygen is a chemical element; it has symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula O
2. Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.
The number π is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although fractions such as are commonly used to approximate it. Consequently, its decimal representation never ends, nor enters a permanently repeating pattern. It is a transcendental number, meaning that it cannot be a solution of an equation involving only finite sums, products, powers, and integers. The transcendence of π implies that it is impossible to solve the ancient challenge of squaring the circle with a compass and straightedge. The decimal digits of π appear to be randomly distributed, but no proof of this conjecture has been found.
A prime number is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1, involve 5 itself. However, 4 is composite because it is a product (2 × 2) in which both numbers are smaller than 4. Primes are central in number theory because of the fundamental theorem of arithmetic: every natural number greater than 1 is either a prime itself or can be factorized as a product of primes that is unique up to their order.
Quantum mechanics is a fundamental theory in physics that describes the behavior of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, quantum field theory, quantum technology, and quantum information science.
In statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. A low standard deviation indicates that the values tend to be close to the mean of the set, while a high standard deviation indicates that the values are spread out over a wider range.
2 (two) is a number, numeral and digit. It is the natural number following 1 and preceding 3. It is the smallest and only even prime number. Because it forms the basis of a duality, it has religious and spiritual significance in many cultures.
4 (four) is a number, numeral and digit. It is the natural number following 3 and preceding 5. It is a square number, the smallest semiprime and composite number, and is considered unlucky in many East Asian cultures.
The Portugal national football team has represented Portugal in men's international football competition since 1921. The national team is controlled by the Portuguese Football Federation (FPF), the governing body for football in Portugal. Portugal's home matches are played at various stadiums throughout Portugal, and its primary training ground and technical headquarters, Cidade do Futebol, is located in Oeiras. The head coach of the team is Roberto Martínez, and the captain is Cristiano Ronaldo, who also holds the team records for most caps and most goals.
The United States men's national soccer team (USMNT) represents the United States in men's international soccer competitions. The team is controlled by the United States Soccer Federation and is a member of FIFA and CONCACAF.
The Mexico national football team represents Mexico in international football and is governed by the Mexican Football Federation. It competes as a member of CONCACAF.
A round-robin tournament is a competition in which each contestant meets every other participant, usually in turn. A round-robin contrasts with an elimination tournament, in which participants/teams are eliminated after a certain number of losses.
The 2011 ICC Cricket World Cup was the tenth Cricket World Cup. It was played in India, Sri Lanka, and for the first time in Bangladesh. India won the tournament, defeating Sri Lanka by 6 wickets in the final at Wankhede Stadium in Mumbai, thus becoming the first country to win the Cricket World Cup final on home soil. India's Yuvraj Singh was declared the man of the tournament. This was the first time in World Cup history that two Asian teams had appeared in the final. It was also the first time since the 1992 World Cup that the final match did not feature Australia.
Thiago Emiliano da Silva is a Brazilian professional footballer who plays as a centre-back for Premier League club Chelsea and the Brazil national team. Widely regarded as one of the greatest defenders of his generation, he is known for his defensive prowess, discipline, and leadership.
The PlayStation 2 (PS2) is a home video game console developed and marketed by Sony Interactive Entertainment. It was first released in Japan on 4 March 2000, in North America on 26 October 2000, in Europe on 24 November 2000, and in Australia on 30 November 2000. It is the successor to the original PlayStation, as well as the second installment in the PlayStation brand of consoles. As a sixth-generation console, it competed with Nintendo's GameCube, Sega's Dreamcast, and Microsoft's Xbox. It is the best-selling video game console of all time, having sold over 155 million units worldwide.
In mathematics, the Pythagorean theorem or Pythagoras' theorem is a fundamental relation in Euclidean geometry between the three sides of a right triangle. It states that the area of the square whose side is the hypotenuse is equal to the sum of the areas of the squares on the other two sides.
The version history of the Android mobile operating system began with the public release of its first beta on November 5, 2007. The first commercial version, Android 1.0, was released on September 23, 2008. The operating system is developed by Google on a yearly cycle since at least 2011. New major releases are announced at Google I/O along with its first public beta to supported Google Pixel devices. The stable version is then released later in the year.
