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the free encyclopedia that anyone can edit. "The Day Before the Revolution" is a science fiction short story by American writer Ursula K. Le Guin (pictured). First published in Galaxy in August 1974, it was republished in Le Guin's The Wind's Twelve Quarters (1975). Set in her fictional Hainish universe, the story has strong connections to her ...
CRISPR (/ˈkrɪspər/) (an acronym for clustered regularly interspaced short palindromic repeats) is a family of DNA sequences found in the genomes of prokaryotic organisms such as bacteria and archaea.[2] These sequences are derived from DNA fragments of bacteriophages that had previously infected the prokaryote. They are used to detect and ...
Wikipedia is a free online encyclopedia that anyone can edit, and millions already have . Wikipedia's purpose is to benefit readers by presenting information on all branches of knowledge. Hosted by the Wikimedia Foundation, it consists of freely editable content, whose articles also have numerous links to guide readers towards more information.
0 (zero) is a number representing an empty quantity. Adding 0 to any number leaves that number unchanged. In mathematical terminology, 0 is the additive identity of the integers, rational numbers, real numbers, and complex numbers, as well as other algebraic structures. Multiplying any number by 0 has the result 0, and consequently, division ...
Viète. de Moivre. Euler. Fourier. v. t. e. In trigonometry, trigonometric identities are equalities that involve trigonometric functions and are true for every value of the occurring variables for which both sides of the equality are defined. Geometrically, these are identities involving certain functions of one or more angles.
ISO 3166-1 ( Codes for the representation of names of countries and their subdivisions – Part 1: Country codes) is a standard defining codes for the names of countries, dependent territories, and special areas of geographical interest. It is the first part of the ISO 3166 standard published by the International Organization for Standardization .
The slash is the oblique slanting line punctuation mark /. It is also known as a stroke, a solidus, a forward slash and several other historical or technical names. Once used to mark periods and commas, the slash is now used to represent division and fractions, exclusive 'or' and inclusive 'or', and as a date separator. A slash in the reverse ...
