327 résultats pour "size"
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James Madison - USA History.
In the spring of 1784 Madison again ran for election to the Virginia assembly, and won. He served nearly three years there, pursuing the same objectives he had foughtfor in Congress. He advocated strengthening the federal government, which was an unpopular position in Virginia, as it was in most of the states. He consistentlysupported measures, at both state and national levels, that would best safeguard the rights of the individual. Madison also continued to oppose any connection betweenchurch...
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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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Boston - geography.
The neighborhoods of Allston and Brighton occupy the northwest corner of the city to the west of Fenway. The Allston-Brighton area is bordered to the east, north, andwest by the Charles River and to the south by the Massachusetts Turnpike and the town of Brookline. It is an industrial and residential neighborhood that is also thelocation of Boston College and Harvard University Business School. Boston has been unsuccessful in annexing Brookline, the birthplace of U.S. president John F.Kennedy an...
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Comet - astronomy.
may exceed the planet Jupiter in size, however. Observations from telescopes on Earth and in space indicate that most of the gases in the coma and tail of a comet are fragmentary molecules, or radicals, of the mostcommon elements in space: hydrogen, carbon, nitrogen, and oxygen. The radicals, for example, of CH, NH, and OH may be broken away from the stable molecules CH 4 (methane), NH 3 (ammonia), and H 2O (water), which may exist as ices or more complex, very cold compounds in the nucleus. Al...
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Jupiter (planet) - astronomy.
Beneath the supercritical fluid zone, the pressure reaches 3 million Earth atmospheres. At this depth, the atoms collide so frequently and violently that the hydrogenatoms are ionized—that is, the negatively charged electrons are stripped away from the positively charged protons of the hydrogen nuclei. This ionization results in asea of electrically charged particles that resembles a liquid metal and gives rise to Jupiter’s magnetic field. This liquid metallic hydrogen zone is 30,000 to 40,000 k...
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Manitoba - Geography.
E Plant Life Forests cover 66 percent of Manitoba. The main forest area is divided into the boreal forest and the mixed-wood forest. The boreal, or northern, forest containsconiferous (cone-bearing) trees, especially white and black spruce, balsam fir, and jack pine. South of the boreal forest is the mixed-wood forest, which contains conifers as well as such deciduous trees as white birch, aspen, poplar, and Manitoba maple. Prairie land is found in the southwest, where the natural vegetation i...
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Manitoba - Canadian History.
E Plant Life Forests cover 66 percent of Manitoba. The main forest area is divided into the boreal forest and the mixed-wood forest. The boreal, or northern, forest containsconiferous (cone-bearing) trees, especially white and black spruce, balsam fir, and jack pine. South of the boreal forest is the mixed-wood forest, which contains conifers as well as such deciduous trees as white birch, aspen, poplar, and Manitoba maple. Prairie land is found in the southwest, where the natural vegetation i...
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Railroads.
III GAUGES The gauge of track is the distance between the inner edges of the rails at points 1.59 cm (0.626 in) below the top of the heads. In the United States, Canada, theUnited Kingdom, Mexico, Norway, Sweden, and much of continental Europe, the standard gauge is 143.51 cm (56.5 in). Why this measurement became the standard isa matter of speculation. Probably the tradition is inherited from early tramroads built to accommodate wagons with axles 1.5 m (5 ft) long; some of the early edge rail...
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Ancient Egypt.
around 4500 BC. The style and decoration of the pottery found at these sites differ from those of pottery found in Upper Egypt. The northern type eventually fell out of use. Other differences between the peoples in Upper Egypt and Lower Egypt include the nature of their architecture and the arrangements for burial of the dead, thelatter perhaps signifying differing religious beliefs. B Unification and Early Dynastic Period By 3500 BC, the settlement of Hierakonpolis, located on the west bank...
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Ancient Egypt - USA History.
around 4500 BC. The style and decoration of the pottery found at these sites differ from those of pottery found in Upper Egypt. The northern type eventually fell out of use. Other differences between the peoples in Upper Egypt and Lower Egypt include the nature of their architecture and the arrangements for burial of the dead, thelatter perhaps signifying differing religious beliefs. B Unification and Early Dynastic Period By 3500 BC, the settlement of Hierakonpolis, located on the west bank...
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Western Philosophy.
the popular belief in personal deities, but he failed to explain the way in which the familiar objects of experience could develop out of elements that are totally differentfrom them. Anaxagoras therefore suggested that all things are composed of very small particles, or “seeds,” which exist in infinite variety. To explain the way in whichthese particles combine to form the objects that constitute the familiar world, Anaxagoras developed a theory of cosmic evolution. He maintained that the activ...
- Fly. Class Insecta Order Diptera Sub Orders Nematocera Brachycera Cyclorrhapha Range Worldwide and in most habitats. Size
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Perception (psychology).
A4 Closure According to the law of closure, we prefer complete forms to incomplete forms. Thus, in the drawing below, we mentally close the gaps and perceive a picture of a duck. This tendency allows us to perceive whole objects from incomplete and imperfect forms. A5 Common Fate The law of common fate leads us to group together objects that move in the same direction. In the following illustration, imagine that three of the balls are moving in one direction, and two of the balls are mo...
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Cat Family - biology.
cats have coats that are mainly brown, yellow, or gray, often with white underbellies. The cubs of many species of cats have spotted coats, which helps hide them ingrass and underbrush from predators. Adult cats that have mainly spotted patterns in their fur include cheetahs, leopards, clouded leopards, jaguars, ocelots, margays, Geoffroy’s cat, and servals. Singlecolor coats are found in lions, pumas, and jaguarundis. Some individuals among leopards and jaguars, and more rarely in other species...
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Atom
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INTRODUCTION
Water Molecule
A water molecule consists of an oxygen atom and two hydrogen atoms, which are attached at an angle of 105°.
spontaneously break apart and change, or decay, into other atoms. Unlike electrons, which are fundamental particles, protons and neutrons are made up of other, smaller particles called quarks. Physicists know of six different quarks.Neutrons and protons are made up of up quarks and down quarks —two of the six different kinds of quarks. The fanciful names of quarks have nothing to do with their properties; the names are simply labels to distinguish one quark from another. Quarks are unique amo...
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Uranus (planet) - astronomy.
V COMPOSITION AND STRUCTURE A Interior of Uranus Uranus contains mostly rock and water, with hydrogen and helium (and trace amounts of methane) in its dense atmosphere. Astronomers believe that Uranus, likeNeptune, formed from the same material—principally frozen water and rock—that composes most of the planet’s moons. As the planet grew, pressures andtemperatures in the planet’s interior increased, heating the planet’s frozen water into a hot liquid. Uranus probably has a relatively small roc...
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Gemstones.
In the late 1960s a method was developed for “growing” diamonds by heating a diamond particle to a high temperature and subjecting it to methane gas. The gasdecomposes into carbon atoms, which adhere to the diamond crystal. The crystal structure of the enlarged diamond is identical to that of a natural diamond. Diamondsof about 1 carat (200 mg or 0.007 oz) have been produced by this method, but their cost is still considerably higher than that of naturally occurring diamonds. Sapphires are made...
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Seal (mammal) - biology.
remote lakes by swimming thousands of kilometers up rivers from the Arctic Ocean. A few other species such as ringed seals and harbor seals have been found livingyear-round in lakes and rivers near the coasts of Russia, Canada, and Alaska. IV DIET OF SEALS Most seals eat fish and sometimes squid. The leopard seal, an Antarctic species, may have the most diverse diet of all, commonly hunting penguins and other seabirds,smaller seals, as well as fish, squid, krill (small shrimplike crustaceans),...
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Butterflies and Moths - biology.
The smallest butterflies are certain blues that have wingspans of a mere 0.7 cm (0.25 in). The largest are the female giant birdwings of Papua New Guinea, whichmeasure up to 30 cm (12 in) across. Moths range in size from tiny Microlepidoptera, several groups of small moths with wings no more than 0.16 cm (0.06 in) across, togiant silk moths, such as the atlas moth, which may exceed 30 cm (12 in) in wingspan. IV REPRODUCTION AND LIFE CYCLE Butterflies locate potential mates by sight, identifyin...
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Chile - country.
D Plant and Animal Life The indigenous plant life of Chile varies according to climatic zone. Plant life in the northern region includes brambles and cactus and has little variety. Here, theAtacama provides one of the best examples on Earth of an absolute desert. The more humid Central Valley supports several species of cacti, espino (a thorny shrub),grasses, and the Chilean pine, which bears edible nuts. Dense rain forests are located south of Valdivia with laurel, magnolia, false beech, and v...
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Native Americans of Middle and South America.
A line that snakes across central Mexico near the Tropic of Cancer forms the northern boundary of Mesoamerica; north of this line rainfall sharply declines and theclimate is much drier. The ancient civilizations of Mesoamerica all arose and developed in the area between this line and the Guatemalan highlands far to the south. Richvolcanic soils are found throughout much of the region. A2 People and Languages Mesoamerica was a great melting pot, home to many peoples and interrelated cultures. In...
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Chemistry - chemistry.
parts of oxygen by weight, which is a ratio of about 1 to 8, regardless of whether the water came from the Mississippi River or the ice of Antarctica. In other words, acompound has a definite, invariable composition, always containing the same elements in the same proportions by weight; this is the law of definite proportions. Many elements combine in more than one ratio, giving different compounds. In addition to forming water, hydrogen and oxygen also form hydrogen peroxide.Hydrogen peroxide h...
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Canada.
Six general landform regions are distinguishable in Canada: the Appalachian Region, the Great Lakes and St. Lawrence Lowlands, the Canadian Shield, the Great Plains,the Canadian Cordillera, and the Canadian Arctic Archipelago. B1 Appalachian Region and Great Lakes and St. Lawrence Lowlands Eastern Canada consists of the Appalachian Region and the Great Lakes and St. Lawrence Lowlands. The Appalachian Region embraces Newfoundland Island, NovaScotia, New Brunswick, Prince Edward Island, and the G...
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Canada - country.
Six general landform regions are distinguishable in Canada: the Appalachian Region, the Great Lakes and St. Lawrence Lowlands, the Canadian Shield, the Great Plains,the Canadian Cordillera, and the Canadian Arctic Archipelago. B1 Appalachian Region and Great Lakes and St. Lawrence Lowlands Eastern Canada consists of the Appalachian Region and the Great Lakes and St. Lawrence Lowlands. The Appalachian Region embraces Newfoundland Island, NovaScotia, New Brunswick, Prince Edward Island, and the G...
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Canada - Canadian History.
Six general landform regions are distinguishable in Canada: the Appalachian Region, the Great Lakes and St. Lawrence Lowlands, the Canadian Shield, the Great Plains,the Canadian Cordillera, and the Canadian Arctic Archipelago. B1 Appalachian Region and Great Lakes and St. Lawrence Lowlands Eastern Canada consists of the Appalachian Region and the Great Lakes and St. Lawrence Lowlands. The Appalachian Region embraces Newfoundland Island, NovaScotia, New Brunswick, Prince Edward Island, and the G...
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Africa.
The highest elevations in Africa are found in the various ranges of East Africa. After Kilimanjaro, the next highest peaks are Mount Kenya (5,199 m/17,057 ft), north ofKilimanjaro in central Kenya; Margherita Peak (5,109 m/ 16,762 ft) in the Ruwenzori Range on the border between Uganda and the Democratic Republic of the Congo(DRC); Ras Dashen (4,620 m/ 15,157 ft) in the Ethiopian Highlands of northern Ethiopia; Mount Meru (4,565 m/ 14,977 ft), close to Kilimanjaro in Tanzania; and MountElgon (4,...
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Africa - Geography.
The highest elevations in Africa are found in the various ranges of East Africa. After Kilimanjaro, the next highest peaks are Mount Kenya (5,199 m/17,057 ft), north ofKilimanjaro in central Kenya; Margherita Peak (5,109 m/ 16,762 ft) in the Ruwenzori Range on the border between Uganda and the Democratic Republic of the Congo(DRC); Ras Dashen (4,620 m/ 15,157 ft) in the Ethiopian Highlands of northern Ethiopia; Mount Meru (4,565 m/ 14,977 ft), close to Kilimanjaro in Tanzania; and MountElgon (4,...
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Automobile.
Electric motors have been used to power automobiles since the late 1800s. Electric power supplied by batteries runs the motor, which rotates a driveshaft, the shaftthat transmits engine power to the axles. Commercial electric car models for specialized purposes were available in the 1980s. General Motors Corporation introduced amass-production all-electric car in the mid-1990s. Automobiles that combine two or more types of engines are called hybrids. A typical hybrid is an electric motor with ba...
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Musical Instruments
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INTRODUCTION
World Music Tour
Click on the instruments to hear music from around the world.
Traditional Timbila of MozambiqueAmong the Chopi, who have lived for centuries along the coast of Mozambique, there is a highly developed tradition ofsongwriting and composing for timbila (xylophone) orchestras. Elaborate migodo (dance suites), interspersed with poeticsongs pertaining to village life, are often performed to these compositions. Timbila music is now recognized as the nationalmusic of Mozambique."Eduardo Durao Mauaia" from Eduardo Durao and Orquestra Durao: Timbila (Cat.# Globestyl...
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Ant - biology.
The workers of many ant species carry a stinger within the hind end of the gaster. These ants use the stinger to defend against their enemies. In some species, workerants lack a stinger but use the tip of their gaster to squirt or dab poison at other small animals and when fighting battles with other ants, fending off predators, or killinginsects or other animals that they use as food. III PHYSIOLOGY Ants have a rigid, external skeleton called an exoskeleton that gives the soft, inner body its...
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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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Dog Family - biology.
muzzles, long and bushy tails, and large ears. Many foxes hunt by stalking prey and then leaping on it with a distinctive, stiff-legged pounce. Once thought to besolitary animals, foxes are now known to live in groups of up to six individuals. The remaining canids are each highly distinctive. Raccoon dogs and bush dogs are the least doglike canids in appearance. Raccoon dogs, found in eastern Asia, havestubby legs, a stout body, short ears, shaggy fur, and a black face mask that resembles a racc...
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Statistics
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INTRODUCTION
Statistics, branch of mathematics that deals with the collection, organization, and analysis of numerical data and with such problems as experiment design and decision
making.
frequency, column (d), is the ratio of the frequency of an interval to the total count; the relative frequency is multiplied by 100 to obtain the percent relative frequency.The cumulative frequency, column (e), represents the number of students receiving grades equal to or less than the range in each succeeding interval; thus, thenumber of students with grades of 30 or less is obtained by adding the frequencies in column (c) for the first three intervals, which total 53. The cumulative relativef...
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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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Horse - biology.
Horses reach sexual maturity at about one and a half years. The estrous cycle in the mare—a mature female horse—typically lasts 21 days. During the first five days ofthe cycle, the mare is usually receptive to mating. The estrous cycle stops during winter and resumes in the spring, which is the start of the breeding season. Astallion—a mature male horse—approaching a mare in estrus engages in various courtship rituals. These include uttering nickering sounds and sniffing and licking themare’s ge...
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Basketball.
rebound. Play continues as the teams score and possession changes. A time-out, when the game is stopped for a certain amount of time, allows coaches to instructplayers or to develop a new game strategy. A Offense Playing offense is perhaps the most prominent part of playing basketball, as it allows players to demonstrate and improve upon individual skills necessary to beingsuccessful. Many of basketball's best players have exceptional talents on offense. Basic offensive skills are passing, ball...
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Poverty.
economic and demographic trends, and (7) welfare incentives. A Overpopulation Overpopulation, the situation of having large numbers of people with too few resources and too little space, is closely associated with poverty. It can result from highpopulation density (the ratio of people to land area, usually expressed as numbers of persons per square kilometer or square mile) or from low amounts of resources, or from both. Excessively high population densities put stress on available resources....
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Dialogue shopping
I would also need a T-shirt. I’m a size 16. Do you have a style in mind? I’d like a plain one. Otherwise I don’t like dark T-shirts. This one is orange… Would you like it? Within this one, I would look like a clown!!! This one is more classical: simply white! Perfect, I think that it is too tight for me, don’t you think so? Have you got a larger one? Yes, of course, here it is. I like it so I take it. Sir, as you buy a lot of articles, I am pleased to offer you this other red T-shirt to thank yo...
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Development (biology) - biology.
Understanding the molecular machinery within cells gives biologists a direct basis for understanding growth, because growth is the synthesis of new protoplasm, andbiologists know the basic mechanism of this synthesis. One key gap, however, exists in this knowledge. Biologists want to know not only how substances aresynthesized but also how growth is controlled so that the proportions of an animal or plant remain consistent from generation to generation. The direction and amountof growth, which a...
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Mercury (planet) - astronomy.
In 1991 powerful radio telescopes on Earth revealed signs of possible deposits of ice in the polar regions of Mercury. These ice deposits occur in areas where sunlightnever falls, such as crater bottoms near both of the planet’s poles. Similar ice deposits may have been found during the 1990s near the poles of the Moon by theClementine and Lunar Prospector spacecrafts. The ice on Mercury likely comes from comets or water-bearing meteorites that have hit Mercury over the planet’s historyup throug...
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Natural Satellite - astronomy.
Titan, Saturn’s largest moon, also has few impact craters. Although icy volcanism from water and ammonia may occur along with some tectonic activity, Titan’s youngsurface is most likely the result of weather processes. Titan’s dense, cold atmosphere precipitates particles of complex organic molecules that accumulate as dunes andmountains. Methane rain erodes the surface and creates lakes at the moon’s poles. Triton’s young surface also may result from processes in its atmosphere, as well aserupt...
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Dog.
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INTRODUCTION
Dog, mammal generally considered to be the first domesticated animal.
French word for butterfly because it has ears that resemble butterfly wings, is a happy, friendly dog, suitable for small living spaces. The final dog group, nonsporting ,includes a wide variety of purebreds that differ in size, coat, overall appearance, and personality, from the shorthaired spotted dalmatian to the curly-haired poodle. V DOG BEHAVIOR Instinctive behaviors of the domestic dog are comparable to those of its wild relatives, the wolf, coyote, fox, and jackal. Unlike trained behavi...
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Dog - biology.
French word for butterfly because it has ears that resemble butterfly wings, is a happy, friendly dog, suitable for small living spaces. The final dog group, nonsporting ,includes a wide variety of purebreds that differ in size, coat, overall appearance, and personality, from the shorthaired spotted dalmatian to the curly-haired poodle. V DOG BEHAVIOR Instinctive behaviors of the domestic dog are comparable to those of its wild relatives, the wolf, coyote, fox, and jackal. Unlike trained behavi...
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Bat - biology.
tomb bat has rather small ears. The shapes of bat ears are extremely varied. The wide ears of the Australian false vampire bat meet above the head and are fused.Many bats are able to turn their ears in the direction of faint noises. Bat hearing and its use in echolocation are highly developed. Some bats have large, conspicuous eyes, while others may have small beady eyes. This variation suggests that vision plays different roles in the lives of various species.Despite the familiar expression, 'b...
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Amphibian (animal) - biology.
strong enough to kill potential predators. C Hearing, Vision, and Vocalizations Amphibians rely on their senses to find food and evade predators. Amphibians lack external ears but have well-developed internal ears. Hearing is most acute in frogs,which typically have a middle ear cavity for transferring sound vibrations from the eardrum, or tympanum, to the inner ear. Frogs and toads also use their keen hearingin communicating with one another. Using a true voice box, or larynx, and a large, exp...
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Gothic Art and Architecture
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INTRODUCTION
Notre Dame Cathedral, Paris
Notre Dame Cathedral, in Paris, was begun in 1163 and completed for the most part in 1250.
and by external arches, called flying buttresses. Consequently, the thick walls of Romanesque architecture could be largely replaced by thinner walls with glass windows,and the interiors could reach unprecedented heights. A revolution in building techniques thus occurred. With the Gothic vault, a ground plan could take on a variety of shapes. The general plan of the cathedrals, however, consisting of a long three-aisled nave interceptedby a transept and followed by a shorter choir and sanctuary,...
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Rock (mineral).
pressure mineral assemblage. In a sense, the rock is stuck in a state that is characteristic of its earlier high-temperature and high-pressure environment. Thus,metamorphic rocks carry with them information about the history of temperatures and pressures to which they were subjected. The size, shape, and distribution of mineral grains in a rock are called the texture of the rock. Many metamorphic rocks are named for their main texture. Textures giveimportant clues as to how the rock formed. As t...
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Arthropod - biology.
through a series of distinct phases to become adults. Larvae may also inhabit different environments and eat different foods than their parents. The life spans ofarthropods range from a few weeks to several decades. V ARTHROPOD EVOLUTION The evolutionary origins of modern arthropods are unclear and complex. It is generally accepted that the phylum is polyphyletic—that is, derived from several separateancestral lines. The ancestors of arthropods were ancient aquatic segmented worms, similar to p...
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Kangaroo - biology.
ungulates, they have evolved multi-chambered stomachs containing bacteria that can break down plant cell walls and release the nutritious cell contents. V SOCIAL ORGANIZATION Kangaroo social life is poorly understood, as few species have been studied in detail. Small species, such as potoroos, bettongs, and musky rat-kangaroos, tend to besolitary and widely dispersed, with a male's territory encompassing those of several females. The animals come together briefly for mating, and mother and offs...
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In-Line Skating.
the foot using a combination of laces and buckles. Many skaters prefer a simple closure system that has laces on the lower portion of the skate and a buckle at the top.The boot liner is made of a soft, padded, cloth portion that fits inside the outer shell. Boot liners should be vented, which keeps the feet cool by allowing perspiration toescape during strenuous workouts or long trips. Attached to the bottom of each skate is the wheel frame. The frame houses from three to five wheels. The wheels...