Zinc, in commerce also spelter, is a chemical element; it has the symbol Zn and atomic number 30. It is the first element of group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is 2. Zinc is the 24th most abundant element in the Earth's crust and has five stable . The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest mineable amounts are found in Australia, A..
A diacritic – also diacritical mark, diacritical point, diacritical sign from ancient Greek διά ( dia, through) and κρίνω ( krinein, to separate) – is a glyph added to a letter, or basic glyph. The term derives from the Greek διακριτικός ( diakritikós, "distinguishing"). Diacritic is primarily an adjective, though sometimes used as a noun, whereas diacritical is only ever an adjective. Some diacritical marks, such as the acute ( ´ ) and grave ( `&thins..
History (from Greek ἱστορία, historia, meaning "inquiry, knowledge acquired by investigation") is the study of the past, specifically how it relates to humans. It is an umbrella term that relates to past events as well as the discovery, collection, organization, and presentation of information about these events. The term includes cosmic, geologic, and organic history, but is often generically implied to mean human history. Scholars who write about history are called . Events occurring prior to wr..
A circle is a simple closed shape in Euclidean geometry. It is the set of all points in a plane that are at a given distance from a given point, the centre; equivalently it is the curve traced out by a point that moves so that its distance from a given point is constant. The distance between any of the points and the centre is called the radius.
Tamil Nadu ( ; ); literally The Land of Tamils or Tamil Country is one of the 29 states of India. Its capital and largest city is Chennai (formerly known as Madras). Tamil Nadu lies in the southernmost part of the Indian Peninsula and is bordered by the union territory of Puducherry and the states of Kerala, Karnataka, and Andhra Pradesh. It is bounded by the Eastern Ghats on the north, by the Nilgiri, the Anamalai Hills, and Kerala on the west, by the Bay of Bengal in the east, by the Gulf of Mannar and..
In the controlled demolition industry, building implosion is the strategic placing of explosive material and timing of its detonation so that a structure collapses on itself in a matter of seconds, minimizing the physical damage to its immediate surroundings. Despite its terminology, building implosion also includes the controlled demolition of other structures, such as , , , and .
Ancient history is the aggregate of past events WordNet Search - 3.0, "History" from the beginning of recorded human history to the Early Middle Ages or the Postclassical Era. The span of recorded history is roughly 5,000 years, with Cuneiform script, the oldest discovered form of coherent writing, from the protoliterate period around the 30th century BC.see Jemdet Nasr period, Kish tablet; see also The Origin and Development of the Cuneiform System of Writing, Samuel Noah Kramer, Thirty Nine Firsts In R..
