494 résultats pour "lowie"
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Tennessee (state) - geography.
The climate of Tennessee is characterized by hot summers, mild winters, and abundant rainfall. C1 Temperature Average July temperatures range from less than 21° C (70° F) in the Blue Ridge region to 27° C (80° F) at Nashville and Memphis. Maximum daytime temperatures insummer often rise above 35° C (95° F) in central and western Tennessee. Daytime temperatures in the mountains rarely rise above 32° C (90° F). Summer nights tendto be warm and muggy in central and western Tennessee, but temperatu...
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Tennessee (state) - USA History.
The climate of Tennessee is characterized by hot summers, mild winters, and abundant rainfall. C1 Temperature Average July temperatures range from less than 21° C (70° F) in the Blue Ridge region to 27° C (80° F) at Nashville and Memphis. Maximum daytime temperatures insummer often rise above 35° C (95° F) in central and western Tennessee. Daytime temperatures in the mountains rarely rise above 32° C (90° F). Summer nights tendto be warm and muggy in central and western Tennessee, but temperatu...
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China - country.
North China lies between the Mongolian Steppe on the north and the Yangtze River Basin on the south. It stretches west from the Bo Hai gulf and the Yellow Sea to theeastern edge of the Tibetan Plateau. Administratively, North China includes Beijing and Tianjin municipalities; Shandong and Shanxi provinces; most of Hebei, Henan,and Shaanxi provinces; and portions of Ningxia Hui Autonomous Region and of Jiangsu, Anhui, and Gansu provinces. Humans have lived in the agriculturally rich region of Nor...
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Nuclear Energy
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INTRODUCTION
Gundremmingen Nuclear Power Plant, Germany
The first of three boiling-water nuclear reactors at Germany's Gundremmingen plant began operating in 1966 but was
permanently shut down after being decommissioned in 1983.
such as ¯U is induced by the absorption of a neutron as in producing cesium-140, rubidium-93, three neutrons, and 200 MeV, or 3.2 × 10 -11 J (7.7 × 10 -12 cal). A nuclear fission reaction releases 10 million times as much energy as is released in a typical chemical reaction. See Nuclear Chemistry. III NUCLEAR ENERGY FROM FISSION The two key characteristics of nuclear fission important for the practical release of nuclear energy are both evident in equation (2). First, the energy per fiss...
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Greece - country.
minerals, such as chromium, copper, uranium, and magnesium, are relatively small. Greece’s small petroleum deposits, located under the Aegean Sea near the island ofThásos, are rapidly being depleted. There are no significant reserves of natural gas. Greece’s forests, probably abundant in ancient times, have been significantly depleted. Subsequent soil erosion has made reforestation efforts difficult. Although muchof Greece’s soil is rocky and dry, the country’s mountains are interspersed with sm...
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Italy - country.
C Natural Resources Italy is poor in natural resources. Much of the land is unsuitable for agriculture because of mountainous terrain or unfavorable climate. Italy, moreover, lacks substantialdeposits of basic natural resources such as coal, iron, and petroleum. Natural gas is the country’s most important mineral resource. Other deposits include feldspar andpumice. Many of Italy’s mineral deposits on the islands of Sicily and Sardinia had been heavily depleted by the early 1990s. Italy is rich...
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Brazil - country.
occasional droughts. Brazil contains a wealth of mineral and plant resources that have not yet been fully explored. It possesses some of the world’s largest deposits of iron ore and containsrich deposits of many other minerals, including gold and copper. Brazil’s fossil fuel resources are modest, but this limitation is offset by the considerable hydroelectricpotential of the nation’s many rivers. Although Brazil is an important producer of tropical crops, areas of highly fertile land are limited...
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Puerto Rico - geography.
the length of the day remains fairly constant throughout the year. San Juan has a mean July temperature of 28°C (83°F) and a mean January temperature of 25°C (77°F). The average temperature of the seawater surrounding theisland is 27°C (81°F), with little variation during the course of the year. The entire island is cooled by the trade winds from the northeast. This air also contains much water vapor. As the air is forced to rise over the mountains, it becomescooler and the water vapor condenses...
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African American History - U.
In their day-to-day lives, slaves and servants shared similar grievances and frequently formed alliances. Advertisements seeking the return of slaves and servants whohad run away together filled colonial newspapers. When a slave named Charles escaped in 1740, the Pennsylvania Gazette reported that two white servants, a 'Scotch man' and an Englishman, escaped with him. Sometimes interracial alliances involved violence. During Bacon's Rebellion in 1676, slaves and servants took up armsagainst Na...
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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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Austria - country.
Wildlife is generally scarce in Austria. Chamois, deer, and marmot are still present; bear, which were once abundant, are now almost completely absent. Hunting isstrictly regulated to protect the remaining species. F Environmental Issues Industrial emissions, a high volume of tourist traffic, and significant air pollution from other countries—principally the former East Germany, Slovakia, and the CzechRepublic—combine to make acid rain the major environmental problem in Austria. One-quarter of...
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Iran - country.
Zagros mountains. In the more arid central part of the country, wild pistachio and other drought-resistant trees grow in areas that have not been disturbed by humanactivity. Tamarisk and other salt-tolerant bushes grow along the margins of the Dasht-e Kavir. A wide variety of native mammals, reptiles, birds, and insects inhabit Iran. Many species of mammals—including wolves, foxes, bears, mountain goats, red mountainsheep, rabbits, and gerbils—continue to thrive. Others—including Caspian tigers,...
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Sound
I
INTRODUCTION
Sound, physical phenomenon that stimulates the sense of hearing.
A fundamental law of harmony states that two notes an octave apart, when sounded together, produce a pleasant-sounding combination. Other combinations of notescan also be pleasing. Physically, an interval of a fifth consists of two notes, the frequencies of which bear the arithmetical ratio 3 to 2, and a major third, the ratio 5 to4. Fundamentally, the law of harmony states that two or more notes sound pleasant when played together if their frequencies bear small, whole number ratios; if thefreq...
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Economics.
Malthus, nature's check was “positive”: “The power of population is so superior to the power of the earth to produce subsistence for man, that premature death must insome shape or other visit the human race.” The shapes it took included war, epidemics, pestilence and plague, human vices, and famine, all combining to level theworld's population with the world's food supply. The only escape from population pressure and the horrors of the positive check was in voluntary limitation of population, no...
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Congo (river) - Geography.
region as Portuguese territory, leaving a marble shaft on the riverbank as proof of his discovery. To Europeans the river became known as the Rio de Padrão (Pillar River). The Kongo king welcomed Cam and subsequent Portuguese explorers and established friendly trading relations with the Portuguese. More than 300 yearselapsed before serious exploration of the Congo was undertaken. Francisco José de Lacerda, a Portuguese explorer, reached the copper-rich Katanga region from the east in 1798, as...
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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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Labor Union.
B The Legal Environment The legal environment, which permits certain types of union activities and prohibits others, also influences the extent of union organization. States with right-to-worklaws have much lower unionization rates than other states. In the United States, the states with the lowest unionization rates are North Carolina, South Carolina, SouthDakota, and Arkansas—states that have right-to-work laws. In 2000 the unionization rate in these states ranged from 4.44 percent to 6.7 per...
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New Brunswick - Geography.
Grand Lake, the largest lake in New Brunswick, is in the lowlands, east of Fredericton. Most other lakes are located in the northern and southwestern parts of NewBrunswick. D Climate New Brunswick has a continental climate that is moderated by maritime influences in the coastal areas. As a result, coastal regions are slightly warmer in the winter andslightly cooler in the summer than are interior regions. Annual temperature variations are large, with the January mean usually at least 25 to 28°C...
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New Brunswick - Canadian History.
Grand Lake, the largest lake in New Brunswick, is in the lowlands, east of Fredericton. Most other lakes are located in the northern and southwestern parts of NewBrunswick. D Climate New Brunswick has a continental climate that is moderated by maritime influences in the coastal areas. As a result, coastal regions are slightly warmer in the winter andslightly cooler in the summer than are interior regions. Annual temperature variations are large, with the January mean usually at least 25 to 28°C...
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Afghanistan - country.
D Climate Most of Afghanistan has a subarctic mountain climate with dry and cold winters, except for the lowlands, which have arid and semiarid climates. In the mountains and afew of the valleys bordering Pakistan, a fringe effect of the Indian monsoon, coming usually from the southeast, brings moist maritime tropical air in summer.Afghanistan has clearly defined seasons: Summers are hot and winters can be bitterly cold. Summer temperatures as high as 49°C (120°F) have been recorded in thenorth...
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Egypt - country.
Egypt has a wide variety of mineral deposits, some of which, such as gold and red granite, have been exploited since ancient times. The chief mineral resource ofcontemporary value is petroleum, found mainly in the Red Sea coastal region, at Al ‘Alamayn (El ‘Alamein) on the Mediterranean, and on the Sinai Peninsula. Otherminerals include phosphates, manganese, iron ore, and uranium. Natural gas is also extracted. D Plants and Animals The vegetation of Egypt is confined largely to the Nile Delta,...
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Turkey - country.
has a general elevation of 900 to 1,500 m (3,000 to 5,000 ft) above sea level. The eastern highlands region is the most mountainous and rugged portion of Turkey; Mount Ararat (Ağrı Da ğı) is the highest peak in the country at 5,165 m (16,945ft). Many Christians and Jews believe it to be the same Mount Ararat mentioned in the Bible as the place where Noah’s ark came to rest. The eastern highlands are thesource for both the Tigris (Dicle) and Euphrates (Fir āt)—two of southwestern Asia’s principal...
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Europe .
D Vegetation Although much of Europe, particularly the west, was originally covered by forest, the vegetation has been transformed by human habitation and the clearing of land.Only in the most northerly mountains and in parts of north central European Russia has the forest cover been relatively unaffected by human activity. On the otherhand, a considerable amount of Europe is covered by woodland that has been planted or has reoccupied cleared lands. The largest vegetation zone in Europe, cuttin...
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Europe - Geography.
D Vegetation Although much of Europe, particularly the west, was originally covered by forest, the vegetation has been transformed by human habitation and the clearing of land.Only in the most northerly mountains and in parts of north central European Russia has the forest cover been relatively unaffected by human activity. On the otherhand, a considerable amount of Europe is covered by woodland that has been planted or has reoccupied cleared lands. The largest vegetation zone in Europe, cuttin...
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Hydrogen - chemistry.
Hydrogen gas does not usually react with other chemicals at room temperature. That is, it does not split into two hydrogen atoms to combine with other chemicals. Thebond between the hydrogen atoms is very strong and can only be broken with a large amount of energy. However, when heated with a flame or a spark, hydrogen gaswill react violently with oxygen in the air to produce water in the following reaction: 2H2 + O 2 → 2H 2O This chemical equation shows that two hydrogen molecules (H 2) and o...
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New France - Canadian History.
the colony now consisted of a governor-general, an intendant , and a Sovereign Council, all located at Québec, with local governors at Trois-Rivières and Montréal, and law courts for all three districts. The senior official was the governor-general, responsible for military matters and for relations with the indigenous nations and theEnglish colonies. The intendant, a noble trained in law, was the official responsible for civil affairs: justice, law enforcement, and the maintenance of the colon...
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Dominican Republic - country.
Manatees and sea turtles also live in Dominican waters. Common birds include blue herons, glossy ibis, flamingos, and brown pelicans. E Environmental Issues Urban dwellers of the Dominican Republic enjoy good access to safe water, but rural communities do not. While current water use is low relative to available resources,water shortages do occur. Although deforestation was once a serious problem in the Dominican Republic, by the beginning of the 21st century, the annual rate of deforestation h...
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North Dakota - geography.
Bismarck, the growing season averages 134 days, as the average date of the last killing frost is May 11 and that of the first killing frost is September 22. The length ofthe growing season drops to about 110 days in the northerly reaches of the state. The long periods of summer sunshine at this latitude, providing as much as 16 hoursof daylight in summer, help crops to mature quickly, thus compensating somewhat for the relatively short growing season. Temperatures in the north are, on the averag...
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North Dakota - USA History.
Bismarck, the growing season averages 134 days, as the average date of the last killing frost is May 11 and that of the first killing frost is September 22. The length ofthe growing season drops to about 110 days in the northerly reaches of the state. The long periods of summer sunshine at this latitude, providing as much as 16 hoursof daylight in summer, help crops to mature quickly, thus compensating somewhat for the relatively short growing season. Temperatures in the north are, on the averag...
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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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Water Cycle.
salt water into groundwater in densely populated low-lying coastal regions. Levees are built to control the course of rivers, and dams are built to render riversnavigable, store water, and provide electrical power. Evaporation of water behind dams is a serious source of water loss. Increasing urbanization has led to more severeflooding because rainwater reaches streams more rapidly and in greater quantity from areas where the ground has been paved. As human population continues to grow, effectiv...
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Beijing - geography.
Shoe Factory in BeijingWorkers assemble shoes at a state-owned factory in Beijing, where rapid industrial development has extended into the city’s outlyingareas in recent years. Beijing is China’s second largest industrial center, after Shanghai.Goh Chaihin/AFP As the nation’s capital and political center, the particular economic role of Beijing has been a topic of considerable debate and controversy. The Communist government hasdesignated Beijing as an appropriate center for industrial, commerc...
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Valley - geography.
B Longitudinal Profile A graph of the slope of a river channel at each point along its course is called a longitudinal profile . In most cases, the slope of a river becomes less steep as it flows from its headwaters to the ocean. Slopes as high as 200 m/km (1000 ft/mi) can be found in mountainous terrain, but slopes of about 2 m/km (10 ft/mi) are more typical in themiddle section of such valleys. Slopes as low as 2 cm/km (1 in/mi) can be found in rivers close to the ocean. In most rivers there...
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Diving (sport).
water that creates a larger, more noticeable splash after the diver’s body displaces water under the surface. To minimize this upjet, top-level divers make a quickswimming motion by releasing their hands and collapsing their arms as they submerge. Instead of a large splash, the surface of the water appears to boil as the airbubbles rise from the diver’s entry. For feetfirst entries, which are rare in top-level competitions, divers place their legs and feet together while pointing their toes down...
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Elephant - biology.
B Trunk An elephant's nose and upper lip are combined in a long, limber trunk, an exceptionally supple appendage with an estimated 150,000 muscles. The versatile trunk actslike a hand for grasping low-growing shrubs and other food and placing it into the mouth; an arm for breaking off tree branches; or a snorkel for breathing when theelephant's body is submerged. Elephants also use their trunks to suck up water and squirt it into their mouths for drinking or over their bodies for bathing. Nostr...
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Molecule - chemistry.
attracted to the negatively charged electrons between them. The electrons belong to the molecule as a whole. However, each hydrogen atom now has a complete outershell of two electrons. The formula H 2 describes a hydrogen molecule, a discrete unit. When a molecule contains just two atoms, such as the hydrogen molecule does, it is called a diatomic molecule. Some atoms can form covalent bonds with more than one other atom and thus create a larger molecule. Atoms form molecules with covalent bo...
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Nova Scotia - Geography.
summer. Nova Scotia receives an average of more than 1,140 mm (45 in) of rain annually, with the Atlantic shore receiving 1,400 mm (55 in) or more. Most of the provincereceives about 1,900 mm (about 70 in) of snow, and considerable winter precipitation comes in the form of rain or ice storms. The average temperature in January, thecoldest month, is generally about -4°C (about 25°F) near the coast and somewhat colder toward the interior. The average temperature in July, the hottest month, isabout...
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Nova Scotia - Canadian History.
summer. Nova Scotia receives an average of more than 1,140 mm (45 in) of rain annually, with the Atlantic shore receiving 1,400 mm (55 in) or more. Most of the provincereceives about 1,900 mm (about 70 in) of snow, and considerable winter precipitation comes in the form of rain or ice storms. The average temperature in January, thecoldest month, is generally about -4°C (about 25°F) near the coast and somewhat colder toward the interior. The average temperature in July, the hottest month, isabout...
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Kenya - country.
threatens fish and other water life in the lake by depriving them of oxygen. Kenya is well known for its game parks—including Masai Mara Game Park and Tsavo National Park in the south, and Marsabit National Reserve in the north—whichattract large numbers of tourists and much revenue. Conservation of wildlife within reserves has thus received high priority. About 13 percent (2007) of Kenya’s totalland is protected. There are 229 (2004) threatened species in Kenya. Threatened habitats include the...
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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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Uzbekistan - country.
E Environmental Issues The evaporation of the Aral Sea is one of the worst ecological disasters in the world. The Aral has shrunk so much that it now holds only about one-fifth the volume ofwater it held in 1960. The shrinkage is due to irrigation withdrawals from the Amu Darya and Syr Darya, a practice that began on a massive scale in the early 1960s aspart of the Soviet Union’s ill-conceived drive to increase cotton yields in Central Asia. Growing cotton in the naturally arid and saline soil...
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Earth (planet).
Milky Way to complete one revolution around the Galaxy’s center. Earth’s axis of rotation is inclined (tilted) 23.5° relative to its plane of revolution around the Sun. This inclination of the axis creates the seasons and causes the height of the Sun in the sky at noon to increase and decrease as the seasons change. The Northern Hemisphere receives the most energy from the Sun when it is tiltedtoward the Sun. This orientation corresponds to summer in the Northern Hemisphere and winter in the S...
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Earth (planet) - astronomy.
Milky Way to complete one revolution around the Galaxy’s center. Earth’s axis of rotation is inclined (tilted) 23.5° relative to its plane of revolution around the Sun. This inclination of the axis creates the seasons and causes the height of the Sun in the sky at noon to increase and decrease as the seasons change. The Northern Hemisphere receives the most energy from the Sun when it is tiltedtoward the Sun. This orientation corresponds to summer in the Northern Hemisphere and winter in the S...
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Thailand - country.
E Natural Resources Thailand possesses a range of mineral resources. Tin is mined in the peninsula. Important gemstones, such as sapphires, are found in the southeast, and coal reserves,particularly lignite, are in the north. Fish are abundant in rivers and coastal waters. In addition to being consumed domestically, fish are also exported. F Climate Thailand experiences a typical monsoon climate. Winds blow from the northeast during the winter months of October to March or April (known as the...
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Reproduction - biology.
E Gestation After fertilization of the egg, the resulting zygote undergoes cell division and differentiation to form the embryo. In most higher plants, the embryo is enclosed in a layerof nutritive material surrounded by a hard outer covering, forming the seed. In most lower animals the embryo, surrounded by the nutritive material of the formerovum, is enveloped by a leathery or calcareous shell and is extruded from the body of the female. Animals, such as birds, that lay their eggs before the...
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Colorado (river, North America) - Geography.
sometime between AD 1300 and 1400, but their descendants, the Hopi and Pueblo people, continue to farm and irrigate using the river's waters. The first European to visit the river was probably Spanish soldier and explorer Francisco de Ulloa, who explored the mouth of the Colorado in 1539. In 1540 and 1541another Spaniard, Francisco Vásquez de Coronado, traveled through much of the region around the Colorado River. An exploring party from the Coronado expedition,led by Garcia López de Cárdenas,...
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Confederation of Canada - Canadian History.
Québec conference seemed in many ways to give Macdonald the centralized union he wanted. The federal government would control banking, finance, defense,transportation, and commerce among the provinces. It would also have far greater powers of taxation than the provincial governments would have. In private,Macdonald predicted that the central government would be so strong that it would soon swallow up the provinces completely. Yet the Québec resolutions were vague or contradictory enough to give...
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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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Comedy
Socrates suffered in the comedy of Aristophanes. Throughout history, opposition to comedy and laughter has been strongest in societies which emphasize physical restraint, decorum and conformity. Many medieval monastic orders had statutes forbidding laughter. The Puritan and Victorian eras saw many condemnations of comedy and laughter. The more authoritarian the regime, the greater its suppression of comedy. Hitler even set up ‘joke courts' to punish those who made fun of his regime - one Berl...