Any of a class of hydrocarbons whose molecules consist only of carbon and hydrogen atoms joined by single covalent bonds (general formula C&math.n;H(2&math.n; + 2)). The simplest is methane (CH4). Alkanes with more than three carbon atoms ...

A contextually specified type of statement: namely, the desired type of response to a question. A distinction is drawn between syntactically independent (What time is it?—It’s four o’clock) and dependent answers, and synt...

"America the Beautiful" is an American patriotic song....

Assistive Computer Technology for Persons with Disabilities The personal computer (PC) can be the backbone of independence for millions of individuals with sensory, physical, and learning disabilities. Computers and information technology ...

Any substance that in water solution tastes sour, changes the colour of acid-base indicators (e.g., litmus), reacts with some metals (e.g., iron) to yield hydrogen gas, reacts with bases to form salts, and promotes certain chemical reactio...

The American National Standards Institute (ANSI) is a private, non-profit organization that serves as the United States administrator and coordinator for the voluntary private-sector standards system. Its statement of purpose is the "enhan...

The Apollo 11 mission was the first manned mission to land on the Moon. It was the fifth human spaceflight of the Apollo program and the third human voyage to the moon. Launched on July 16, 1969, it carried Commander Neil Alden Armstrong, C...

designation, derived from the Greek words for “star” and “sailor,” commonly applied to an individual who has flown in outer space. More specifically, astronauts are those persons who went to space aboard a U.S. spac...

Any of the six chemical elements in the leftmost group of the periodic table (lithium, sodium, potassium, rubidium, cesium, and francium). They form alkalies when they combine with other elements. Because their atoms have only one electron...

Number of a chemical element in the systematic, ordered sequence shown in the periodic table. The elements are arranged in order of increasing number of protons in the nucleus of the atom (the same as the number of electrons in the neutral...

Russian film director Andrei Tarkovsky (1932--1986) was, arguably, the greatest filmmaker of his nation. While perhaps not the innovator that fellow Russian Sergei Eisenstein was, Tarkovsky nevertheless imbued each of his films with a poet...

Animals are multicellular, heterotrophic eukaryotes. Because animals are unable to make their own food, they must have some means of ingesting food. They do this by consuming plants, other animals, or decomposing organic matter, or by abso...

The aardwolf (Proteles cristatus) is a small insectivorous hyena-like mammal, native to Eastern and Southern Africa. The name means "earth wolf" in Afrikaans.[2] It is also called "maanhaar-jackal" and "protelid". Unlike other hyenas (subfa...

Some bold adventurers disdain The limits of their little reign, And unknown regions date descry. . . . and now expecting Each hour their great adventurer, from the search Of foreign words. He who has not an adventure has not horse or mule,...

Species of agave (Agave americana), of Mexico and the southwestern U.S. It takes many years (from five to 100) to mature, flowers only once, and then dies. It is widely cultivated for its large spiny leaves and enormous flower cluster, and...

Early U.S. constitution (1781–89) under the government by the Continental Congress, replaced in 1787 by the U.S. Constitution. It provided for a confederation of sovereign states and gave the Congress power to regulate foreign affair...

Whoever would undertake the formidable task of writing the intellectual history of the twentieth century would be well advised to include in it the works of Arthur Koestler and the controversies they helped to spawn. These controversies we...

The German philosopher Arthur Schopenhauer (1788-1860), whose pessimistic philosophy was widely known in the late 19th century in Europe and the United States, held that ultimate reality was nothing but senseless striving or will, having n...

Angola is located on the South Atlantic Coast of West Africa between Namibia and the Republic of the Congo. It also is bordered by the Democratic Republic of the Congo and Zambia to the east. The country is divided into an arid coastal stri...

This article is part of the series: Politics and government ofAngola...

This article is about communications in Angola: if (window.showTocToggle) { var tocShowText = "show"; var tocHideText = "hide"; showTocToggle(); } Telephone Telephone service is limited mostly to government and business use. 96,300 main lin...

The Angolan Armed Forces (FAA) is headed by a Chief of Staff who reports to the Minister of Defense. There are three divisions, the Army, Navy (Marinha de Guerra, MdG), and Air and Air Defense Forces (FAPA). Total manpower is about 110,000....

Morale is faith in the man at the top....

Androids are mechanical, or otherwise artificial, creations in the shape of humans. They have long been a staple of science fiction. From the clockwork persons of myth to Isaac Asimov's humanoid robots, to Star Wars's C-3PO, ...

Military firearm that is chambered for ammunition of reduced size or propellant charge and has the capacity to switch between semiautomatic and fully automatic fire. Light and portable, yet able to deliver a high volume of fire with reason...