2432 résultats pour "from"
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Mexico City - geography.
The park houses some of Mexico's most important public buildings, including Chapultepec Castle. Construction of the castle began in 1783. Positioned on the park’shighest elevation, the castle functioned as a fortress during colonial times. It once served as the presidential residence and now houses the National Museum of History,which includes murals by 20th-century Mexican painter Juan O'Gorman. Los Pinos, the official residence and working offices of the president, is also on the grounds, buti...
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Iraq - country.
The Euphrates begins in Turkey, crosses Syria, and enters Iraq at Abū Kam āl. The flow of the Euphrates into Iraq has been greatly reduced by dams built by Turkeyand Syria. The gradient of the Euphrates above the town of H īt, in west central Iraq, is steep. In the 2,640 km (1,640 mi) from its source in Turkey to H īt, the river fallsfrom 3,000 m (10,000 ft) to a low water elevation of 50 m (170 ft) above sea level, an average drop of 1 m per km (6 ft per mi). In Iraq below H īt the fall is very...
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Yemen - country.
port. Al Ḩudaydah (155,110), in the Tih āmah, is the second largest port. Ta‘izz, (178,043), in the highlands above Aden, is an important commercial and light industrialcenter. Among Yemen’s larger towns are Şa‘dah, far to the north; Dham ār, Yarim, and Ibb, in the middle region; Al Mukall ā, on the southern coast; and in Hadhramaut,the towns of Shib ām, Say‘ ūn, and Tar īm. C Language Nearly all Yemenis speak Arabic. However, the country’s extremely rugged terrain, widely separated population...
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Plate Tectonics.
ridges. The Mid-Atlantic Ridge is an underwater mountain range created at a divergent plate boundary in the middle of the Atlantic Ocean. It is part of a worldwidesystem of ridges made by seafloor spreading. The Mid-Atlantic Ridge is currently spreading at a rate of 2.5 cm per year (1 in per year). The mid-ocean ridges today are60,000 km (about 40,000 mi) long, forming the largest continuous mountain chain on earth. Earthquakes, faults, underwater volcanic eruptions, and vents, oropenings, along...
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Yangtze - Geography.
A Agriculture and Industry Today about 400 million people, or about one-third of the population of China, live in the Yangtze Basin. Many are engaged in agriculture. The basin contributes nearlyhalf of China’s crop production, although only one-quarter of the basin is arable. The most fertile areas for farming are the Sichuan Basin, the plains between theYangtze and its tributary the Han, and the plains of the lower basin. In all about 40 percent of the cereals, more than 30 percent of the cott...
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Warfare.
organizations as the League of Nations in 1920 and the United Nations in 1945, and détente (suggested for scaling down the cold war). See Arms Control. Modern antiwar sentiment and organized peace movements are derived in large part from the beliefs of religious sects such as the Society of Friends and the MennoniteChurch. The first peace societies in history were established in the U.S. in 1815, and since then pacifists have actively opposed wars and conscription, and promoted thecause of con...
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Extrasolar Planets - astronomy.
When a planet passes in a front of the star it orbits—an event called a transit—it causes a small dip in the brightness of the star. Measuring the slight change in thebrightness can be used not only to directly detect a planet, but to determine its size and orbit. However, the planet needs to orbit in a plane that lies in a telescope’sline of sight on the star. Despite long odds, Earth-based telescopes have detected and studied a few exoplanets using this method. The first space telescope design...
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São Paulo (city) - geography.
universities include the State University Paulista Júlio de Mesquita Filho (1976), and the even larger University of São Paulo (1934), which incorporates the city’s famousand influential Faculty of Law. Important private universities are Mackenzie University, originally founded by Presbyterian missionaries from the United States (1870);the Paulista University (1972); the Pontifical Catholic University of São Paulo (1946); and the University São Judas Tadeu (1971). The city is home to the São Pau...
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San Antonio (city, Texas) - geography.
The SBC Center is the home venue for the San Antonio Spurs of the National Basketball Association (NBA) and the San Antonio Silver Stars of the Women's NationalBasketball Association (WNBA). The dome also serves as the site for the Alamo Bowl, an annual post-season college football game. Large themed amusement parks inthe San Antonio area are Fiesta Texas and Sea World of Texas. San Antonio’s major annual event is the Fiesta, a ten-day celebration in late April with carnivals, ethnic feasts, art...
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Vietnam - country.
E Natural Resources Vietnam’s most valuable natural resource is its land, particularly the fertile, alluvial soils in the Red and Mekong deltas. Some 29 percent of the land is currently beingcultivated. Vietnam has some valuable mineral resources, including gold, iron, tin, zinc, phosphate, chromite, apatite, and anthracite coal. Most deposits are located in the northernpart of the country. Few attempts were made to extract these minerals until the French takeover of Vietnam at the end of the 1...
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Cuban Missile Crisis.
inspect ships to determine whether they were carrying weapons. Kennedy warned that if Khrushchev fired missiles from Cuba, the result would be “a full retaliatoryresponse upon the Soviet Union.” Because international law defines a blockade as an act of war, Kennedy and his advisers decided to refer to the blockade as a quarantine. The United States wassupported by other members of the Organization of American States, an organization of nations in the western hemisphere that seek to cooperate on...
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Cuban Missile Crisis - U.
inspect ships to determine whether they were carrying weapons. Kennedy warned that if Khrushchev fired missiles from Cuba, the result would be “a full retaliatoryresponse upon the Soviet Union.” Because international law defines a blockade as an act of war, Kennedy and his advisers decided to refer to the blockade as a quarantine. The United States wassupported by other members of the Organization of American States, an organization of nations in the western hemisphere that seek to cooperate on...
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Insect - biology.
they almost always have six legs. In some insects, such as beetles, the legs are practically identical, but in other insects each pair is a slightly different shape. Still otherinsects have specialized leg structures. Examples are praying mantises, which have grasping and stabbing forelegs armed with lethal spines, and grasshoppers andfleas, which have large, muscular hind legs that catapult them into the air. Mole crickets’ front legs are modified for digging, and backswimmers have hind legs de...
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Egyptian Art and Architecture - USA History.
The kings of the 1st Dynasty (2920 BC-2770 BC) were buried in the cemetery of their ancestors at Abydos in southern Egypt. Their burial sites were built of mud brick (bricks baked in the sun) and consisted of two parts: a tomb in the desert where the king was buried, and a rectangular funerary enclosure at the desert's edge, whererituals were performed. A pair of stone slabs called stelae marked the tombs and bore the name of the royal occupant. In the 2nd Dynasty (2770 BC-2649 BC), most r...
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Human Sexuality.
About six weeks after conception, if a Y chromosome is present in the embryo's cells (as it is in normal males), a gene on the chromosome directs the undifferentiatedgonads to become testes. If the Y chromosome is not present (as in normal females), the undifferentiated gonads will become ovaries. If the gonads become testes, they begin to produce androgens (male hormones, primarily testosterone) by about eight weeks after conception. These androgens stimulate development of the one set of the...
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Cell (biology) - biology.
proteins, or other proteins required by the cell. While relatively simple in construction, prokaryotic cells display extremely complex activity. They have a greater range of biochemical reactions than those found in theirlarger relatives, the eukaryotic cells. The extraordinary biochemical diversity of prokaryotic cells is manifested in the wide-ranging lifestyles of the archaebacteria andthe bacteria, whose habitats include polar ice, deserts, and hydrothermal vents—deep regions of the ocean un...
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Bear - biology.
programs sponsored by zoos or other breeding centers have attempted to breed giant pandas in captivity, although most of these programs have proved unsuccessful.Among the difficulties faced by captive breeders has been the problem of encouraging a female giant panda to mate with a selected male during the two to three daysof the year when she is most fertile, a period known as estrus. B Spectacled Bear Creamy-white rings surrounding the eyes give the spectacled bear its name. Its shaggy coat of...
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World Energy Supply.
In the 1990s, oil production by non-OPEC countries remained strong and production by OPEC countries rebounded. The result at the end of the 20th century was aworld oil surplus and prices (when adjusted for inflation) that were lower than in 1972. Experts are uncertain about future oil supplies and prices. Low prices have spurred greater oil consumption, and experts question how long world petroleum reservescan keep pace with increased demand. Many of the world’s leading petroleum geologists beli...
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Honolulu - geography.
of Brigham Young University. The state’s largest museum, the Bernice Pauahi Bishop Museum, is located in Honolulu. It contains a large collection of Polynesian archaeological artifacts, as well asmany exhibits on Hawaiian history and culture. The museum also has an extensive entomological collection with more than 13 million specimens. Other importantmuseums include the Honolulu Academy of Arts, known for its extensive collection of Japanese, Chinese, and Korean art; the Contemporary Museum, wit...
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Crusades.
modern Lebanon; the Principality of Antioch, in modern Syria; and the County of Edessa, in modern northern Syria and southern Turkey. IV CRUSADES OF THE 12TH CENTURY The Crusades of the 12th century, through the end of the Third Crusade in 1192, illustrate the tensions and problems that plagued the enterprise as a whole. For thelords of Outremer a compromise with the residents and Muslim powers made sense; they could not live in constant warfare. And yet as European transplants theydepended on...
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Crusades .
modern Lebanon; the Principality of Antioch, in modern Syria; and the County of Edessa, in modern northern Syria and southern Turkey. IV CRUSADES OF THE 12TH CENTURY The Crusades of the 12th century, through the end of the Third Crusade in 1192, illustrate the tensions and problems that plagued the enterprise as a whole. For thelords of Outremer a compromise with the residents and Muslim powers made sense; they could not live in constant warfare. And yet as European transplants theydepended on...
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Christmas.
The new custom of Christmas gift giving allowed the marketplace to exert an unprecedented influence on holiday celebrations. Commercial innovations such asdepartment stores and mass advertising further expanded the custom of exchanging Christmas gifts. Seasonal retail sales helped fuel the economy, causing merchantsand advertisers to become some of the season’s most ardent promoters. Many holiday celebrants regretted these changes, however, and began voicing the nowcommon lament that Christmas h...
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Evolution - biology.
genetic diversity to extinction. Sexual reproduction ensures that the genes in a population are rearranged in each generation, a process termed recombination. Although the combinations of genes inindividuals change with each new generation, the gene frequency, or ratio of different alleles in the entire population, remains relatively constant if no evolutionaryforces act on the population. One such force is the introduction of new genes into the genetic material of the population, or gene pool...
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Armenian Massacres .
Some of the Armenian revolutionaries and others hoped that the massacres would provoke the intervention of the European powers (Britain, France, Austria-Hungary,and Germany). Although the leaders of the European powers publicly condemned the actions of the sultan, they failed to intervene. Mutual rivalries and suspicions, aswell as the imprecise terms of Article 61 of the Treaty of Berlin, helped produce this inaction. But these bloody episodes soon paved the way for the rise of a newnationalist...
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Political Parties in the United States.
quickly enabled the Republican Party to overpower the Know-Nothings. Although the Republicans lost their first campaign for the presidency in 1856, they triumphed in1860 with former congressman Abraham Lincoln. The Republican victory resulted in part from the division of the Democratic Party into Northern and Southern factions,each of which ran its own presidential candidate, and in part from their success at attracting Whigs and Know-Nothings who had opposed the Republicans in 1856.During the C...
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Political Parties.
In both Britain and the United States, competition between political parties undermined traditional conceptions of politics rooted in classical and Christian notions ofvirtue and public service. According to this tradition, political leaders should act according to a model of virtue that involved placing the common good above theinterests of a fraction of the society. Leaders acting to benefit only themselves or a narrow portion of the society were considered corrupt. However, party competitionr...
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Tajikistan - country.
by more than 100 percent due to a high birth rate and improvements in medical care. During the early 1990s, however, the growth rate began to decline due to civilwar and emigration. A Ethnic Groups and Languages Tajiks constitute the largest ethnic group in Tajikistan, making up about 65 percent of the population. The peoples who live in Gorno-Badakhshan, located in the Pamirs,are classified as Tajiks, although their languages and customs are distinct. The largest minority group in the country...
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Bangladesh - country.
F Environmental Issues Waterborne diseases such as cholera are a serious threat to public health in Bangladesh. Until the 1970s, many of Bangladesh’s people became sick from drinkingpolluted water drawn from surface rivers. Aid agencies such as the United Nations Children’s Fund (UNICEF) built shallow wells throughout the country to help provide asafe source of drinking water to Bangladesh’s poor. In the 1990s, however, it was discovered that many of these wells were contaminated by arsenic, a...
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Antarctica - Geography.
The maximum area of sea ice surrounding Antarctica each winter varies from year to year. A marked decline during the 1970s appears to have reversed in more recentdecades, except in the Antarctic Peninsula area. This area has lost almost 40 percent of its sea ice since the start of the 1980s. Sea ice is important to marine life. Krillfeed on algae that live under the sea ice and are released when the ice melts in spring and summer. In turn, many marine animals feed on krill. Emperor penguinsbreed...
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Light
I
INTRODUCTION
Light, form of energy visible to the human eye that is radiated by moving charged particles.
simulates the action of a moving charge upon the electric field. It creates a wave that travels along the rope in a direction that is perpendicular to the initial up anddown movement. Because electromagnetic waves are transverse—that is, the vibration that creates them is perpendicular to the direction in which they travel, they are similar to waveson a rope or waves traveling on the surface of water. Unlike these waves, however, which require a rope or water, light does not need a medium, or su...
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United States History - U.
and improved upon the designs of Arab sailing ships and learned to mount cannons on those ships. In the 15th century they began exploring the west coast ofAfrica—bypassing Arab merchants to trade directly for African gold and slaves. They also colonized the Madeira Islands, the Azores, and the Cape Verde Islands andturned them into the first European slave plantations. The European explorers were all looking for an ocean route to Asia. Christopher Columbus sailed for the monarchs of Spain in 149...
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United States History - U.
and improved upon the designs of Arab sailing ships and learned to mount cannons on those ships. In the 15th century they began exploring the west coast ofAfrica—bypassing Arab merchants to trade directly for African gold and slaves. They also colonized the Madeira Islands, the Azores, and the Cape Verde Islands andturned them into the first European slave plantations. The European explorers were all looking for an ocean route to Asia. Christopher Columbus sailed for the monarchs of Spain in 149...
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Battle of Waterloo.
In the meantime, Grouchy had failed to overtake Blücher's army. At about 10 PM on June 17, Grouchy's scouts informed him that the Prussians, instead of retreating east to Namur, had turned northwest, seeking apparently a juncture with Wellington. Grouchy's message of warning to Napoleon brought the reply, sent at 10 AM on June 18, that Grouchy should keep trying to make contact with the Prussians. Grouchy's pursuit was slovenly and unhurried, and he failed to locate the enemy. On the morning o...
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Saskatchewan (province) - Geography.
The length of the frost-free season varies within the province. In the southwest, particularly in the valley lands along the South Saskatchewan River, the frost-freeperiod ranges from 150 to 160 days. Regina enjoys about 123 frost-free days, and Saskatoon has about 111. The far north has only from 85 to 95 frost-free days. One important characteristic of Saskatchewan’s climate is the great variability in temperature and precipitation from year to year, which is often critical for agriculture.The...
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Saskatchewan (province) - Canadian History.
The length of the frost-free season varies within the province. In the southwest, particularly in the valley lands along the South Saskatchewan River, the frost-freeperiod ranges from 150 to 160 days. Regina enjoys about 123 frost-free days, and Saskatoon has about 111. The far north has only from 85 to 95 frost-free days. One important characteristic of Saskatchewan’s climate is the great variability in temperature and precipitation from year to year, which is often critical for agriculture.The...
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Republic of Indonesia - country.
Mahakam in East Kalimantan and the Martapura and Barito in South Kalimantan. Most of these rivers originate in the island’s central massif (mountain mass) and meander through extensive swamps as they approach the coast. Settlements such as Samarinda and Banjarmasin cluster along the rivers, which serve ascommunication routes into the interior. The largest rivers on Sumatra drain from west to east into the Strait of Malacca. In the north, the Asahan River once linked trade between the Batak peo...
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Reconstruction (U.
Instead, Congress began a lengthy debate over Reconstruction policy. The program eventually enacted resulted from a series of compromises among Republicanfactions; the Radicals were never powerful enough to gain everything they sought. Still, fueled by anger at the president's refusal to compromise and at the appearanceof former Confederates returning to power throughout the South, members of Congress moved increasingly toward the Radicals. The key Reconstruction measuresenacted aimed to produce...
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Orthodox Church.
formally defined by an ecumenical council, as it was in Catholicism, some Orthodox theologians have taught that the act of becoming a monk or the service of burial canalso be sacraments. The sacramental practice of the Orthodox differs in many details from Western customs. Baptism is administered by immersing the child or adult three times under thewater, each time in the name of one of the persons of the Trinity. It is followed immediately by anointment with chrism, a sacred perfumed oil that r...
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Cuba - country.
Only two land mammals, the hutia, or cane rat, and the solenodon, a rare insectivore that resembles a rat, are known to be indigenous. The island has numerous batsand nearly 300 kinds of birds, including vultures, wild turkeys, quail, finches, gulls, macaws, parakeets, and hummingbirds. The bee hummingbird of Cuba is thesmallest bird in the world. Among the few reptiles are tortoises, caimans, the Cuban crocodile, and a species of boa that can attain a length of 3.7 m (12 ft). More than700 speci...
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Spider (arthropod) - biology.
The spider’s abdomen is soft and saclike. On the underside of the tip of the abdomen are three pairs of spinnerets. Each spinneret is studded with many fine, hairliketubes called spigots, which produce a variety of silk threads. The spigots lead to several large silk glands inside the abdomen. Silk is formed as a liquid inside theseabdominal glands. As the silk is drawn out through the spigots, protein molecules within the silk line up parallel to one another, causing the silk to harden and form...
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Federal Republic of Germany - country.
B Rivers and Lakes Rivers have played a major role in Germany’s economic development. The Rhine River flows in a northwesterly direction from Switzerland through much of westernGermany and The Netherlands into the North Sea. It is a major European waterway and a pillar of commerce and trade. Its primary German tributaries include theMain, Mosel, Neckar, and Ruhr rivers. The Oder (Odra) River, along the border between Poland and Germany, runs northward and empties into the Baltic; it provides an...
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Crafts.
VI POTTERY Ceramic objects can be molded completely by hand or thrown (shaped) on a potter's wheel, a device with a rotating horizontal disk. When the clay hardens, it is fired ina high-temperature oven, or kiln, to strengthen it. To make the object waterproof, glazes may then be applied and the piece fired again. Although hand construction iseasy to master, throwing on the potter's wheel requires practice. Several simple tools are used by potters, including sponges, trimming tools, wooden sha...
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Kansas City (Missouri) - geography.
Major institutions of higher education in Kansas City are a branch (established in 1929) of the University of Missouri, Avila College (1916), Rockhurst College (1910),DeVry Institute of Technology (Missouri) (1931), and the Kansas City Art Institute (1885). Schools in neighboring suburbs include Park University (1875), in Parkville,and William Jewell College (1849), in Liberty. Baptist, Nazarene, and Methodist theological schools are also located in the area. Midwest Research Institute, one of t...
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Africa - history.
Africa’s other major mountainous regions occur at the northern and southern fringes of the continent. The Atlas Mountains, a system of high ranges, extend for 2,200 km(1,400 mi) across Morocco, Algeria, and Tunisia, roughly parallel to the northern coast. These ranges enclose a number of broad inland basins and plateaus. In the west, theHigh (or Grand) Atlas contains Toubkal (4,165 m/ 13,665 ft), the highest peak of the system. Toward the east, the Atlas consists of two parallel ranges: the Tell...
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Togo - country.
corn, millet, and sorghum. The leading export crops are coffee, cotton, groundnuts, and cacao. Livestock, chiefly sheep and goats, are raised on the northern plateau.Fish are caught in Togo’s rivers and in the Gulf of Guinea. B Mining and Manufacturing Togo is a leading producer of phosphates, which are by far the country’s most significant mineral product. In 2004, 400,000 metric tons of phosphate rock were mined.Industrial activity is limited but growing. The leading manufactures include ceme...
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Wireless Communications.
were large, heavy units. After the invention of the transistor in 1948, radios shrank in size to small handheld radio transceivers. Public two-way radios with severalfrequency options are widely available as well. Usually limited in range to a few miles, these units are great aids for such mobile professionals as construction workers,film crews, event planners, and security personnel. Simpler two-way radios, called walkie-talkies, have been popular children’s toys for years. Most walkie-talkiesb...
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Census.
Prior to any census, a census agency must develop an accurate list of addresses and maps to ensure that everyone is counted. The U.S. Census Bureau obtainsaddresses primarily from the United States Postal Service and from previous census address lists. It also works closely with state, local, and tribal governments tocompile accurate lists. Finally, census agencies often conduct an extensive marketing campaign before Census Day to remind the general population about theimportance of responding t...
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Child Development.
developmental scientists have studied how cultural values guide the skills and attitudes that children acquire as they mature, and how brain maturation influences thedevelopment of thinking and feeling. For a more detailed discussion of child development theories, see the Theories of Child Development section of this article. III BASIC QUESTIONS A Nature and Nurture Scholars have long debated the relative importance of nature (hereditary influences) and nurture (environmental influences) i...
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Gambling.
C Lotteries Lotteries are another form of gambling. In a lottery, tickets are sold for a set amount and a share of the proceeds is returned to the winners, usually through a randomdraw. Most games allow players to pick their own numbers or let a computer randomly pick for them. Lotteries offer a wide variety of games, including weekly drawings,instant “scratch” tickets, daily games, and superlottos with prizes increasing until there is a winner. Large lottery prizes sometimes exceed $100 millio...
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Native American Architecture.
B Relationship to the Universe and Nature A more profound difference between European American and Native American perceptions lay in how human beings saw themselves in relationship to the universe andin what they believed their responsibilities were to the natural world and to each other. Most European Americans saw themselves as separate from creation andadversaries of nature, ever struggling to conquer and subdue nature and force it to yield to their will. Native Americans saw themselves as...
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