50 résultats pour "channel"
- Channel Islands National Park.
- Hell espont (Dardanelles) Greek The long narrow channel or strait leading from the Aegean Sea into the Sea of Marmara and the Black Sea.
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River.
IV RIVER PATTERNS River patterns, or general shapes, depend on the geologic zone and the climate of the location. There are four river patterns: meandering, braided, anastomosing, andstraight. A meandering pattern follows a winding, turning course. A braided pattern has connected channels that resemble a hair braid. An anastomosing river patterncombines features of the meandering and braided patterns. Some river patterns are simply straight channels. Meandering and braided are the most common...
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River - Geography.
IV RIVER PATTERNS River patterns, or general shapes, depend on the geologic zone and the climate of the location. There are four river patterns: meandering, braided, anastomosing, andstraight. A meandering pattern follows a winding, turning course. A braided pattern has connected channels that resemble a hair braid. An anastomosing river patterncombines features of the meandering and braided patterns. Some river patterns are simply straight channels. Meandering and braided are the most common...
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River - geography.
In very large rivers, the water comes from rain that may have fallen as far as 6,000 km (4,000 mi) away. During the journey through rills and streams, the water’s flowmay erode and deposit sediment in the river’s channel and on its floodplain ( see Erosion; Deposit). The biggest rivers usually carry the largest amount of sediment. Yet some of the largest rivers may carry very little sediment because the watershed may not have a lot of sediment. A river carries the most sediment when the flow is...
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Mars (planet) - astronomy.
The Martian core is probably much like Earth’s, consisting mostly of iron, with a small amount of nickel. If other light elements, particularly sulfur, exist there as well, thecore may be larger than presently thought. From studying Earth’s magnetic field and core, scientists theorize that the motions of the liquid rock in Earth’s core generateits magnetic field. Mars does not have a significant magnetic field, so scientists believe that Mars’s core is probably solid. However, spacecraft data in...
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Television.
A charge-coupled device (CCD) can be much smaller than a camera tube and is much more durable. As a result, cameras with CCDs are more compact and portablethan those using a camera tube. The image they create is less vulnerable to distortion and is therefore clearer. In a CCD, the light from a scene strikes an array ofphotodiodes arranged on a silicon chip. Photodiodes are devices that conduct electricity when they are struck by light; they send this electricity to tiny capacitors. Thecapacitors...
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Houston - geography.
Prominent historical and cultural institutions include the Civic Center Complex, located in the central business district. The complex is composed of the George R. BrownConvention Center; the Wortham Center, which is the home of the Houston Grand Opera and the Houston Ballet; and the Jesse H. Jones Hall for Performing Arts, whichis the home of the Houston Symphony. The nearby Alley Theatre houses a professional repertory acting company. Among other local professional performance groupsare the Ma...
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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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Valley.
Except in mountainous terrain, rivers are almost always flanked by floodplains. Floodplains are flat wide deposits of alluvium, river-deposited sediment, on either side of the river channel. During floods, a river overflows its banks and spreads out the sediment near the river to form a floodplain. Floodplains of large rivers, such as thoseof the Mississippi River, can be flat areas tens of kilometers across. River channels migrate back and forth across their floodplains as alluvium is repeate...
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Valley - Geography.
Except in mountainous terrain, rivers are almost always flanked by floodplains. Floodplains are flat wide deposits of alluvium, river-deposited sediment, on either side of the river channel. During floods, a river overflows its banks and spreads out the sediment near the river to form a floodplain. Floodplains of large rivers, such as thoseof the Mississippi River, can be flat areas tens of kilometers across. River channels migrate back and forth across their floodplains as alluvium is repeate...
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D-Day Invasion.
The Allied planners focused on the beaches around Caen and the Cotentin Peninsula in northern France rather than those of Calais, even though it meant the forcewould be crossing at a wider part of the English Channel. That disadvantage was far outweighed by what the site offered: comparatively scanty defensive fortificationsand beachhead ideally suited for successful exits. The clincher was an isolated battlefield that the Germans would have difficulty reinforcing. The date was set for May 1, 19...
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France - country.
In both the Paris and Aquitaine basins, fertile soils derived from limestone and wind-deposited dust, called loess, have supported prosperous agriculture since ancienttimes. Other lowlands in France are scattered and relatively small. They include the Alsace Plain in the east, bordering Germany, the valley of the Rhône River in thesoutheast, and the Languedoc Plain along the Mediterranean coast. A2 Uplands France contains several regions of uplands, the worn down remains of ancient mountain sys...
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Great Lakes - Geography.
of 1972 and 1978, have focused on water-quality problems in the Great Lakes. The International Joint Commission on the Great Lakes, established under the BoundaryWaters Treaty, implements and oversees these agreements and has limited authority to regulate obstructions or diversions of boundary waters that would affect thenatural level or flow of lake waters. B Exotic Species The fish populations of the lakes have changed dramatically in the 20th century; changes were wrought at first by overfis...
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Telecommunications.
commonly referred to as wireless communications, use technologies such as cordless telephones, cellular radio telephones, pagers, and satellites. Wirelesscommunications offer increased mobility and flexibility. In the future some experts believe that wireless devices will also offer high-speed Internet access. C Wires and Cables Wires and cables were the original medium for telecommunications and are still the primary means for telephone connections. Wireline transmission evolved fromtelegraph...
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California - geography.
The Basin and Range province is an arid area of mountain ranges, basins, and deserts. In California it is represented primarily by parts of the Great Basin and SonoranDesert sections. Within the Great Basin lies Death Valley, whose lowest elevation, 86 m (282 ft) below sea level, is the lowest point in the Western Hemisphere. TheSonoran Desert section is characterized by numerous flat plains separated by low but rugged ranges. It includes the extensive Mojave, or Mohave, Desert. Also in thisprov...
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California - USA History.
The Basin and Range province is an arid area of mountain ranges, basins, and deserts. In California it is represented primarily by parts of the Great Basin and SonoranDesert sections. Within the Great Basin lies Death Valley, whose lowest elevation, 86 m (282 ft) below sea level, is the lowest point in the Western Hemisphere. TheSonoran Desert section is characterized by numerous flat plains separated by low but rugged ranges. It includes the extensive Mojave, or Mohave, Desert. Also in thisprov...
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Panama Canal - geography.
LockA lock is a section of a waterway enclosed by gates at either end to allow ships to be raised or lowered to a different water level. Inthis example, a ship enters the upper level and the gates close behind it. The water is then allowed to drain into the lower level,lowering the water level of the lock and the ship. When the water level of the lock equals the level of the lower canal, the lower gateswill open and the ship can proceed.© Microsoft Corporation. All Rights Reserved. The canal’s 1...
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Dwight D.
maneuvers in Louisiana in 1941, he played a leading role as a staff officer, adding to his reputation and securing him a promotion to brigadier general. On December 7,1941, Japan attacked Pearl Harbor, Hawaii, and the next day the United States entered World War II against the Axis Powers (Japan, Germany, and Italy). A weeklater, the army’s new chief of staff, General George C. Marshall, called Eisenhower to Washington, D.C., and put him in charge of the War Plans Division. Opinions differed on...
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Florida - USA History.
accidentally introduced into the region in the 1880s, and it spread with alarming rapidity throughout the upper reaches of the river. The plant is very difficult toeradicate, and it has also clogged the channels of other Florida rivers. To increase drainage of the Everglades, which drain naturally to Florida Bay and the Gulf ofMexico, a number of drainage channels and canals have been built across southern Florida. Among the rivers flowing from the peninsula to the Gulf of Mexico are the Suwanne...
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Moon - astronomy.
B Volcanic Features Maria, domes, rilles, and a few craters display indisputable characteristics of volcanic origin. Maria are plains of dark-colored rock that cover approximately 40 percent ofthe Moon's visible hemisphere. The maria formed when molten rock erupted onto the surface and solidified between 3.16 billion and 3.96 billion years ago. This rockresembles terrestrial basalt, a volcanic rock type widely distributed on Earth, but the rock that formed the maria has a higher iron content an...
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Missouri - geography.
Saint Francois Mountains, at the eastern end of the crest of the dome. Only in these mountains have the sedimentary rocks been sufficiently eroded away so that theunderlying igneous rocks are exposed. They form the rounded, knoblike peaks of an old mountain range. The peaks project, in isolation or in clusters, between 230 and300 m (750 and 1,000 ft) above the surrounding sedimentary basins. One of these knobs, Taum Sauk Mountain, reaches 540 m (1,772 ft) above sea level and is thehighest point...
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Missouri - USA History.
Saint Francois Mountains, at the eastern end of the crest of the dome. Only in these mountains have the sedimentary rocks been sufficiently eroded away so that theunderlying igneous rocks are exposed. They form the rounded, knoblike peaks of an old mountain range. The peaks project, in isolation or in clusters, between 230 and300 m (750 and 1,000 ft) above the surrounding sedimentary basins. One of these knobs, Taum Sauk Mountain, reaches 540 m (1,772 ft) above sea level and is thehighest point...
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Alaska - geography.
depression surrounded by highlands and have the coldest winter and hottest summer temperatures in Alaska. Once the Kuskokwim River passes through theKuskokwim Mountains, it forms the southern edge of a vast lake-studded alluvial plain bounded on the north by the Yukon River. This water-logged lowland is a majorsummer nesting area for birds. Fairbanks is the major city in this region, while Fort Yukon is the major community in the Yukon Flats and Bethel the largest settlementon the Lower Kuskokwi...
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Alaska - USA History.
depression surrounded by highlands and have the coldest winter and hottest summer temperatures in Alaska. Once the Kuskokwim River passes through theKuskokwim Mountains, it forms the southern edge of a vast lake-studded alluvial plain bounded on the north by the Yukon River. This water-logged lowland is a majorsummer nesting area for birds. Fairbanks is the major city in this region, while Fort Yukon is the major community in the Yukon Flats and Bethel the largest settlementon the Lower Kuskokwi...
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World War II .
the Nazi-Soviet Pact was signed. In the part published the next day, Germany and the Soviet Union agreed not to go to war against each other. A secret protocol gaveStalin a free hand in Finland, Estonia, Latvia, eastern Poland, and eastern Romania. See also German-Soviet Nonaggression Pact. III MILITARY OPERATIONS In the early morning hours of September 1, 1939, the German armies marched into Poland. On September 3 the British and French surprised Hitler by declaring war onGermany, but they...
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Panama Canal - Geography.
The size of ships using the Panama Canal has steadily increased. About 27 percent of the vessels that use the canal are built to the maximum dimensions that can passthrough it (a category called “Panamax”). This has prompted further widening of Gaillard Cut, so that the larger Panamax vessels may transit safely. However, some ofthe world’s commercial and military ships are too large for the canal. Since the 1940s, new U.S. battleships and aircraft carriers have been built exceeding the canal’sdi...
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Bowling.
In each of the first nine frames the bowler rolls one or two balls. If the bowler knocks down all ten pins with the first ball, he or she has rolled a strike, the best roll possible. An X is recorded on the scoresheet or screen, and the bowler receives ten points (the number of pins knocked down) plus a bonus of the number of pins thebowler knocks down in his or her next two bowls. The maximum possible score in a strike frame, therefore, is 30: the strike followed by two more strikes on subseq...
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Britischer Film.
Thematisch und stilistisch weit ihrer Zeit voraus waren Anthony Asquith’ The Browning Version (1951; Konflikt des Herzens ) und Michael Powells Peeping Tom (1960; Peeping Tom ). Diese Filme ebneten den Weg für die britische „New Wave” und das Kino der „Angry young men”. 3 DER MODERNE BRITISCHE FILM 1956 hatte John Osborne mit seinem skandalisierten Theaterstück Look Back in Anger den Generationenbruch auf der Bühne vollzogen. Gleichzeitig forderte die Bewegung „Free Cinema” künstlerisch...
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Marketing.
Where advertising reaches a mass audience, personal or direct selling focuses on one customer at a time. That kind of individual attention makes direct sellingexpensive, but it also makes it effective. As the costs of personal selling have risen, the utilization of salespeople has changed. Simple transactions are completed byclerks. Salespeople are now used primarily where the products are complex and require detailed explanation, customized application, or careful negotiation over priceand paym...
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MEDIA : Les médias
Television : La télévision
A colour television set
A cartoon : un dessin anim éA serial : un feuilleton The se quel : la suite A n episode : un épisode A thriller : un fil m à suspense A wa r fil m : un film de guerre A T V addict : un mordu de télé To be hoo ked by : être accroché par To be glued to : être collé à To be riveted to the screen : être rivé à l’écran To encroach upon f ami ly life : empié ter sur la vie de fa mille Ho w can y ou possibility relax in front o f a TV screen? : Com ment peux- tu te dét...
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Le Royaume Uni, les USA
La Grande Bretagne
Britain
Les îles britanniques
The British
Edimbourg Edinburgh La Ta mise Th e Th ames La mer du Nord Th e North Sea La Manche Th e (english) Channel Le Pas-de-Calais Th e Straits o f Dover Les Iles anglo- normandes Th e Channe l islands Une colonie A colon y La mère patrie Th e mother country Émigrer To emigrate S’établir To settle Un colon A settler L’empire colonial Th e Empire L’autonomie Autonom y, self-governmen tAutonome Self-governing Le Common wealth Th e Common wealth Le Canada Canada L’Australie Australia La...
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Houston - geography.
Medical Research in HoustonThe city of Houston in southeastern Texas is home to the Texas Medical Center, a complex of more than 40 medical institutions. Inthis Medical Center laboratory, a scientist operates a DNA synthesizer in research aimed at developing a vaccine to protect againstHIV.Hank Morgan-Science Source/Photo Researchers, Inc. Situated near major petroleum and natural-gas fields, Houston is the center of the national petroleum industry. The metropolitan region leads the nation in pe...
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Mississippi (river) - Geography.
Contributed By:William H. RenwickMicrosoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
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Shanghai - geography.
language. V EDUCATION AND CULTURE Shanghai is one of China’s leading centers of learning and culture. The metropolitan area is home to more than 40 institutions of higher learning. These include some ofChina’s most famous universities, such as Fudan University (founded in 1905), Tongji University (1907), and the East China Normal University (1951). A large branch ofthe Chinese Academy of Sciences is located in Shanghai, and extensive research is undertaken in areas such as semiconductors, laser...
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Reproductive System.
in which the young develop, and a thinner channel, the vagina, which opens exteriorly. V GENITALS In animals that lay their eggs and discharge their sperm into water, the spermatozoa reach the eggs by chemical attraction; the eggs of individuals of a species attractonly the sperm of members of the same species. When eggs and sperm are deposited at great distances from each other, the number of eggs fertilized is small. Manyamphibians and aquatic vertebrates solve this problem by attaching thems...
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Hundred Years' War.
knowledge of English tactics. Du Guesclin became Constable of France (head of the army) in 1370, and when he died in 1380, Clisson succeeded him. Charles also reorganized the French military, developing a full-time, professional army for the first time, and established a regular system of taxation to pay for it. Inaddition, France gained an important ally on the throne of the Spanish kingdom of Castile, Henry II, who had pledged support for Charles V. When the Caroline war began in 1369, the Eng...
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Hundred Years' War .
knowledge of English tactics. Du Guesclin became Constable of France (head of the army) in 1370, and when he died in 1380, Clisson succeeded him. Charles also reorganized the French military, developing a full-time, professional army for the first time, and established a regular system of taxation to pay for it. Inaddition, France gained an important ally on the throne of the Spanish kingdom of Castile, Henry II, who had pledged support for Charles V. When the Caroline war began in 1369, the Eng...
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Sewage Disposal.
greater load on the piping system and the treatment plant. The amount of storm-water drainage to be carried away depends on the amount of rainfall as well as on the runoff or yield of the watershed ( see Drainage). A typical metropolitan area discharges a volume of wastewater equal to about 60 to 80 percent of its total daily water requirements, the rest being used for washingcars and watering lawns, and for manufacturing processes such as food canning and bottling. B Composition The composi...
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Iran-Iraq War - History.
The Iranian offensives of 1982 set a pattern that continued for the rest of the war. Exploiting their superiority in numbers, Iran sent its Revolutionary Guard on theattack, supported by regular military forces. Outnumbered Iraqi forces inflicted heavy losses on the Iranians but ultimately fell back. As soon as the initial Iranian thrusthad exhausted itself, however, the Iraqi army exploited Iranian disorganization and lack of equipment to retake much of the lost territory. As the war continued,...
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Radio.
signal, such as a musical note. This form of modulation, AM, is used in many radiotelephony services including standard radiobroadcasts. AM is also employed for carriercurrent telephony, in which the modulated carrier is transmitted by wire, and in the transmission of still pictures by wire or radio. See Broadcasting, Radio and Television. In FM the frequency of the carrier wave is varied within a fixed range at a rate corresponding to the frequency of a sound signal. This form of modulation, p...
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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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First Americans.
bones and artifacts helped 19th-century archaeologists establish the age of ancient human encampments in Europe. Yet, search as they might, American archaeologists found no comparable evidence of a Pleistocene-era human presence. But several sites revealed stone artifacts thatsome scholars believed looked similar to the ancient stone tools found in Europe. On the basis of this similarity, these experts claimed the American artifacts must be asold. By the 1890s, however, other scholars had challe...
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First Americans - Canadian History.
bones and artifacts helped 19th-century archaeologists establish the age of ancient human encampments in Europe. Yet, search as they might, American archaeologists found no comparable evidence of a Pleistocene-era human presence. But several sites revealed stone artifacts thatsome scholars believed looked similar to the ancient stone tools found in Europe. On the basis of this similarity, these experts claimed the American artifacts must be asold. By the 1890s, however, other scholars had challe...
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Qing Dynasty - History.
The Manchus also dealt with the problem of Russian expansion into northeastern Asia. In 1689 the Treaty of Nerchinsk was signed by an envoy from the Manchu courtand a Russian representing Peter the Great. The treaty, the first between China and a Western country, established territorial boundaries and defined rules ofcommerce for the two powers. Through the mid-18th century, the Manchus continued to consolidate their power. In 1720 the Qing ruler sent forces to fight the Mongols in Tibet and the...
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Los Angeles - geography.
(2006 population, 472,494), located east of the Port of Los Angeles. The city of Compton (95,701) is located north of Long Beach, on the east side of the AlamedaCorridor. On the other side of the corridor are the cities of Torrance (142,350) and Inglewood (114,914). Northwest of Inglewood and west of downtown Los Angeles are the wealthy and fashionable Santa Monica (88,050) and Beverly Hills (34,979). Both cities are enclaves:Santa Monica is surrounded by the City of Los Angeles to the north, ea...
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Los Angeles - geography.
(2006 population, 472,494), located east of the Port of Los Angeles. The city of Compton (95,701) is located north of Long Beach, on the east side of the AlamedaCorridor. On the other side of the corridor are the cities of Torrance (142,350) and Inglewood (114,914). Northwest of Inglewood and west of downtown Los Angeles are the wealthy and fashionable Santa Monica (88,050) and Beverly Hills (34,979). Both cities are enclaves:Santa Monica is surrounded by the City of Los Angeles to the north, ea...
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Ancient Rome .
attributed to Numa, including the selection of virgins to be priestesses of the goddess Vesta. He also established a calendar to differentiate between normal workingdays and those festival days sacred to the gods on which no state business was allowed. His peaceful reign lasted from 715 to 673 BC. Under Tullus Hostilius (672–641 BC) the Romans waged an aggressive foreign policy and began to expand their lands by the conquest of nearby cities like Alba Longa. When the warlike King Hostilius co...
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Ancient Rome - USA History.
attributed to Numa, including the selection of virgins to be priestesses of the goddess Vesta. He also established a calendar to differentiate between normal workingdays and those festival days sacred to the gods on which no state business was allowed. His peaceful reign lasted from 715 to 673 BC. Under Tullus Hostilius (672–641 BC) the Romans waged an aggressive foreign policy and began to expand their lands by the conquest of nearby cities like Alba Longa. When the warlike King Hostilius co...
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United Kingdom - country.
B Natural Regions and Topography The island of Great Britain can be divided into two major natural regions—the highland zone and the lowland zone. The highland zone is an area of high hills andmountains in the north and west. The lowland zone in the south and east consists mostly of rolling plains. The zones are divided by an imaginary line running throughEngland from the River Exe on the southwest coast to the mouth of the River Tees on the northeast coast. The lowland zone has a milder climat...