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Munsey's Magazine was an American magazine founded by Frank Munsey in 1889. Originally launched in 1889 as Munsey's Weekly, it became an illustrated monthly in 1891, printing both fiction and non-fiction. In 1893 the price was reduced from 25 to 10 cents and circulation rose to more than 250,000 issues. The same year Munsey became one of the ...
The Lockheed U-2, nicknamed " Dragon Lady ", is an American single- engine, high altitude reconnaissance aircraft operated from the 1950s by the United States Air Force (USAF) and the Central Intelligence Agency (CIA). It provides day and night, high-altitude (70,000 feet, 21,300 meters), all-weather intelligence gathering. [1]
In mathematics, the trigonometric functions (also called circular functions, angle functions or goniometric functions) [1] [2] are real functions which relate an angle of a right-angled triangle to ratios of two side lengths.
The High-frequency Active Auroral Research Program ( HAARP) is a University of Alaska Fairbanks program which researches the ionosphere – the highest, ionized part of Earth's atmosphere .
The Su-57 is the first aircraft in Russian military service designed with stealth technology and is intended to be the basis for a family of stealth combat aircraft.
The number π (/paɪ/; spelled out as "pi") 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 ...
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.
