usefully
91Group theory — is a mathematical discipline, the part of abstract algebra that studies the algebraic structures known as groups. The development of group theory sprang from three main sources: number theory, theory of algebraic equations, and geometry. The… …
92Whistle — A simple whistle is a woodwind instrument which produces sound from a stream of forced air.Many types exist, from small police and sports whistles (also called pea whistles), to much larger train whistles, which are steam whistles specifically… …
93Reason — involves the ability to think, understand and draw conclusions in an abstract way, as in human thinking. The meaning of the word reason overlaps to a large extent with rationality and the adjective of reason in philosophical contexts is normally… …
94Big Bang nucleosynthesis — In physical cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than those of H 1 (i.e. the normal, light isotope of hydrogen, whose nuclei consist of a single proton each) during the early …
95The Selfish Gene — Infobox Book name = The Selfish Gene title orig = translator = image caption = Original cover from the painting The Expectant Valley by zoologist Desmond Morris author = Richard Dawkins illustrator = cover artist = country = language = series =… …
96Edward Albee — Infobox Writer name = Edward Albee caption = Edward Albee, photographed by Carl Van Vechten, 1961 birthdate = birth date and age|mf=yes|1928|3|12 birthplace = Washington D.C. occupation = Dramatist nationality = American period = 1958 present… …
97Embedded system — Picture of the internals of an ADSL modem/router. A modern example of an embedded system. Labelled parts include a microprocessor (4), RAM (6), and flash memory (7). An embedded system is a computer system designed to do one or a few dedicated… …
98Caesarean section — Intervention A team of obstetricians performing a Caesarean section in a modern hospital. ICD 9 CM …
99Aquifer — Typical aquifer cross section An aquifer is a wet underground layer of water bearing permeable rock or unconsolidated materials (gravel, sand, or silt) from which groundwater can be usefully extracted using a water well. The study of water flow… …
100Transistor–transistor logic — (TTL) is a class of digital circuits built from bipolar junction transistors (BJT), and resistors. It is called transistor–transistor logic because both the logic gating function (e.g., AND) and the amplifying function are performed by… …
