234 résultats pour "amount"

• West Virginia - USA History.

  Forests, mostly of hardwood varieties, cover 79 percent of West Virginia. The principal commercial species are the oak, yellow poplar, maple, birch, beech, black walnut,hickory, and gum. Softwoods include pines and hemlock firs. Flowering trees include the wild crab apple, dogwood, hawthorn, and redbud. Among the many floweringbushes and plants are the rhododendron, which is the state flower, the laurel, blueberry, hepatica, wild geranium, and black-eyed Susan. Insects and disease, mostly introd...

• Kansas - geography.

  at the adjoining cities of Kansas City, Kansas, and Kansas City, Missouri. Its chief headstreams are the Republican and Smoky Hill rivers, which join to form the KansasRiver at Junction City. Each of the headstreams has numerous tributaries. The Kansas River proper is only 270 km (170 mi) long, but the Smoky Hill River has a lengthof 870 km (540 mi), and the Republican River has a length of 720 km (450 mi). The main tributary flowing into the Kansas River is the Big Blue River. The Arkansas Rive...

• Kansas - USA History.

  at the adjoining cities of Kansas City, Kansas, and Kansas City, Missouri. Its chief headstreams are the Republican and Smoky Hill rivers, which join to form the KansasRiver at Junction City. Each of the headstreams has numerous tributaries. The Kansas River proper is only 270 km (170 mi) long, but the Smoky Hill River has a lengthof 870 km (540 mi), and the Republican River has a length of 720 km (450 mi). The main tributary flowing into the Kansas River is the Big Blue River. The Arkansas Rive...

• 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...

• New York - geography.

  The Adirondack province consists of a large highland area occupying 26,000 sq km (10,000 sq mi) in the northeastern quarter of the state. The region is domelike inshape, with the higher elevations toward the east. The western Adirondack province is more a rugged hill region and not truly mountainous. Geologically, this area isrelated to the Laurentian Upland, or Canadian Shield, which lies north of the St. Lawrence River, for it is composed of the same very old igneous rocks, principallygranite...

• New York - USA History.

  The Adirondack province consists of a large highland area occupying 26,000 sq km (10,000 sq mi) in the northeastern quarter of the state. The region is domelike inshape, with the higher elevations toward the east. The western Adirondack province is more a rugged hill region and not truly mountainous. Geologically, this area isrelated to the Laurentian Upland, or Canadian Shield, which lies north of the St. Lawrence River, for it is composed of the same very old igneous rocks, principallygranite...

• Roman Empire .

  A Government Augustus did not derive his power from any single office, but from the authority of his name and his victory. In fact, he carefully pieced together a patchwork of powersthat allowed him to be an absolute ruler and yet avoid the hatred Caesar aroused as dictator. In Latin, the name Augustus implies both political authority and religiousrespect. The Romans had for some time called Octavian imperator , a title once awarded to victorious generals that soon became associated with the r...

• Roman Empire - History.

  A Government Augustus did not derive his power from any single office, but from the authority of his name and his victory. In fact, he carefully pieced together a patchwork of powersthat allowed him to be an absolute ruler and yet avoid the hatred Caesar aroused as dictator. In Latin, the name Augustus implies both political authority and religiousrespect. The Romans had for some time called Octavian imperator , a title once awarded to victorious generals that soon became associated with the r...

• 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...

• Helium - chemistry.

  the bends. This synthetic atmosphere is also used in medicine to relieve sufferers of respiratory difficulties because helium moves more easily than nitrogen throughconstricted respiratory passages. In surgery, beams of ionized helium from synchrocyclotron sources are proving useful in treating eye tumors, by stabilizing or evenshrinking the tumors. Such beams are also used to shrink blood-vessel malformations in the brains of patients. Helium is used in inert-gas arc welding for light metals, s...

• Thermodynamics I INTRODUCTION Thermodynamics, field of physics that describes and correlates the physical properties of macroscopic systems of matter and energy.

  Carnot EngineThe idealized Carnot engine was envisioned by the French physicist Nicolas Léonard Sadi Carnot, who lived during theearly 19th century. The Carnot engine is theoretically perfect, that is, it converts the maximum amount of energy intomechanical work. Carnot showed that the efficiency of any engine depends on the difference between the highest andlowest temperatures reached during one cycle. The greater the difference, the greater the efficiency. An automobileengine, for example, wou...

• Coronary Heart Disease.

  when a patient is at rest may indicate that the blood supply of the heart is not normal, and the ECG can often detect damage from a previous heart attack. In anexercise stress test, an ECG is recorded while a patient is performing physical activity such as walking on a treadmill or riding a stationary bicycle. As the intensity ofexercise increases, the doctor looks for specific changes in the ECG that indicate the heart is not getting enough oxygen. In cardiac catheterization, a long, thin, flex...

• Greenhouse Effect.

  addition, humans cut down huge tracts of trees for lumber or to clear land for farming or building. This process, known as deforestation, can both release the carbonstored in trees and significantly reduce the number of trees available to absorb carbon dioxide. As a result of these human activities, carbon dioxide in the atmosphere is accumulating faster than Earth’s natural processes can absorb the gas. By analyzing airbubbles trapped in glacier ice that is many centuries old, scientists have d...

• Acid Rain.

  the Adirondack Mountains of New York State, a quarter of the lakes and ponds are acidic, and many have lost their brook trout and other fish. In the middleAppalachian Mountains, over 1,300 streams are afflicted. All of Norway’s major rivers have been damaged by acid rain, severely reducing salmon and trout populations. E Plants and Animals The effects of acid rain on wildlife can be far-reaching. If a population of one plant or animal is adversely affected by acid rain, animals that feed on tha...

• Electronics.

  electronic circuits. The resistors are made from carbon mixtures, metal films, or resistance wire and have two connecting wires attached. Variable resistors, with anadjustable sliding contact arm, are often used to control volume on radios and television sets. E Capacitors Capacitors consist of two metal plates that are separated by an insulating material ( see Capacitor). If a battery is connected to both plates, an electric charge will flow for a short time and accumulate on each plate. If th...

• Neptune (planet) - astronomy.

  The gaseous atmosphere of Neptune contains hydrogen, helium, and about 3 percent methane. It extends about 5,000 km (about 3,000 mi) above the planet’s ocean.Light reflected from Neptune’s deep atmosphere is blue, because the atmospheric methane absorbs red and orange light but scatters blue light. In 1998 astronomersalso identified molecules of methyl in Neptune’s atmosphere. Methyl molecules each contain one carbon atom and three hydrogen atoms. Methyl molecules are knownas hydrocarbon radical...

• Money.

  A Early Monetary Regulations In the American colonies, coins of almost every European country circulated, with the Spanish dollar predominating. Because of the scarcity of coins, the colonists alsoused various primitive mediums of exchange, such as bullets, tobacco, and animal skins. Many of the colonies issued paper money that circulated at varying rates ofdiscount. The first unified currency consisted of the notes issued by the Continental Congress to finance the American Revolution. These no...

• Optics I INTRODUCTION Mirage Mirages appear because differences in air temperature cause light rays from an object to take different paths to a viewer's eye.

  Refraction of Light by DiamondsThe brilliance of diamonds is due to their high refractive index, a measure of how strongly a transparent material bendslight rays. The skill of the gem-cutter lies in angling the facets of the stone so that each light ray entering it is reflectedmany times before it emerges again.Spencer Grant/Photo Researchers, Inc. The amount of light reflected depends on the ratio of the refractive indexes for the two media. The plane of incidence contains the incident ray and...

• Industrial Revolution I INTRODUCTION Industrial Revolution, widespread replacement of manual labor by machines that began in Britain in the 18th century and is still continuing in some parts of the world.

  The most important advance in iron production occurred in 1784 when Englishman Henry Cort invented new techniques for rolling raw iron, a finishing process thatshapes iron into the desired size and form. These advances in metalworking were an important part of industrialization. They enabled iron, which was relativelyinexpensive and abundant, to be used in many new ways, such as building heavy machinery. Iron was well suited for heavy machinery because of its strength anddurability. Because of t...

• Industrial Revolution .

  The most important advance in iron production occurred in 1784 when Englishman Henry Cort invented new techniques for rolling raw iron, a finishing process thatshapes iron into the desired size and form. These advances in metalworking were an important part of industrialization. They enabled iron, which was relativelyinexpensive and abundant, to be used in many new ways, such as building heavy machinery. Iron was well suited for heavy machinery because of its strength anddurability. Because of t...

• Heart.

  situation. A Cardiac Cycle Although the right and left halves of the heart are separate, they both contract in unison, producing a single heartbeat. The sequence of events from the beginning ofone heartbeat to the beginning of the next is called the cardiac cycle. The cardiac cycle has two phases: diastole, when the heart’s chambers are relaxed, and systole,when the chambers contract to move blood. During the systolic phase, the atria contract first, followed by contraction of the ventricles. T...

• 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...

• 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...

• Wyoming (state) - geography.

  The basins, which lie in the rain shadow of mountains, are very dry, with an average annual precipitation of about 250 mm (about 10 in) or less; the Great Plains regionhas an annual average of about 380 mm (about 15 in), and the Black Hills region receives slightly more. Thunderstorms and hailstorms are relatively frequent insummer. The annual snowfall ranges from about 500 mm (about 20 in) in the Bighorn Basin to well over 5,100 mm (over 200 in) in the higher mountains, where annualprecipitatio...

• Wyoming (state) - USA History.

  The basins, which lie in the rain shadow of mountains, are very dry, with an average annual precipitation of about 250 mm (about 10 in) or less; the Great Plains regionhas an annual average of about 380 mm (about 15 in), and the Black Hills region receives slightly more. Thunderstorms and hailstorms are relatively frequent insummer. The annual snowfall ranges from about 500 mm (about 20 in) in the Bighorn Basin to well over 5,100 mm (over 200 in) in the higher mountains, where annualprecipitatio...

• Israel (country) - country.

  harbor in the northern part of the country, and Ashdod, an artificial deepwater port to the south, serve as the main seaports on the Mediterranean. The port of Elat onthe Gulf of Aqaba provides Israel’s only access to the Red Sea, making it extremely important to the country’s shipping interests. D Natural Resources Although much of Israel’s desert regions contain poor soils, the northern Negev, the coastal plains, and the interior valleys provide patches of productive soils. Anestimated 18 per...

• shakespear

  · Bassanio wants to borrow three thousand ducats, but both he and Lorenzo have been   unsuccessful in getting a friend to lend him the amount. So he has come to the   moneylender, Shylock · Bassanio wants to borrow three thousand ducats, but both he and Antonio have been   unsuccessful in getting a friend to lend him the amount. So he has come to the   moneylender, Shylock Q.5 What has Bassanio already told him? · Bassanio has already explained the terms of the loan to Shylock · Bassanio has alr...

• Atlantic Ocean - Geography.

  the Atlantic than in the other oceans. A remarkable example of plant life is found in the Sargasso Sea, the oval section of the North Atlantic lying between the West Indies and the Azores and bounded onthe west and north by the Gulf Stream. Here extensive patches of brown gulfweed ( Sargassum ) are found on the relatively still surface waters. Actively mined mineral resources in the Atlantic include titanium, zircon, and monazite (phosphates of the cerium metals), off the eastern coast of Flori...

• Nova - astronomy.

  When first discovered, the spectrum of a nova shows that the expanding layers of gas that cause the brightening have temperatures of 40,000° to 50,000° C (70,000°to 90,000° F)—about eight times as hot as the surface of the Sun. By the time a nova reaches maximum brightness, the temperature of the material has fallen to about10,000° C (about 20,000° F), or lower. Just after maximum brightness, the escaping cloud of gas cools and expands enough to become transparent. This transparency allows astro...

• Ice Ages.

  B Future Ice Ages The record of previous glacial activity is the best indicator for future ice ages. Scientists examine the evidence for the numerous 100,000-year glacial-interglacial cycleswithin the present ice age to attempt a forecast of future ice ages. Since all previous ice ages lasted tens of millions of years, our present ice age will likely continue fora considerable amount of time. Each glaciation begins slowly and may take 80,000 years or more to reach its maximum extent. A rapid me...

• Pollination - biology.

  rapidly as in cross-pollination, because one plant with a beneficial gene can transmit it only to its own offspring and not to other plants. Self-pollination evolved laterthan cross-pollination, and may have developed as a survival mechanism in harsh environments where pollinators were scarce. IV POLLEN TRANSFER Unlike animals, plants are literally rooted to the spot, and so cannot move to combine sex cells from different plants; for this reason, species have evolved effectivestrategies for ac...

• Big Bang Theory - astronomy.

  hydrogen atoms. Hydrogen atoms can only absorb and emit specific colors, or wavelengths, of light. The formation of atoms allowed many other wavelengths of light,wavelengths that had been interfering with the free electrons prior to the cooling of the universe, to travel much farther than before. This change set free radiation thatwe can detect today. After billions of years of cooling, this cosmic background radiation is at about 3 K (-270°C/-454°F).The cosmic background radiation was first d...

• Hormone.

  women is called a follicle-stimulating hormone. When a follicle-stimulating hormone binds to an ovary cell, it stimulates the enzymes needed for the synthesis ofestradiol, a female sex hormone. Another gonadotropin called luteinizing hormone regulates the production of eggs in women and the production of the male sexhormone testosterone. Produced in the male gonads, or testes, testosterone regulates changes to the male body during puberty, influences sexual behavior, and playsa role in growth. T...

• Water Pollution.

  Cryptosporidium in the water supply of Milwaukee, Wisconsin, sickened more than 400,000 people and killed more than 100. H Thermal Pollution Water is often drawn from rivers, lakes, or the ocean for use as a coolant in factories and power plants. The water is usually returned to the source warmer than when itwas taken. Even small temperature changes in a body of water can drive away the fish and other species that were originally present, and attract other species in placeof them. Thermal pol...

• Turbine.

  steam turbine has supplanted the reciprocating engine as a prime mover in large electricity-generating plants and is also used as a means of jet propulsion. Steam turbines are used in the generation of nuclear power and in nuclear ship propulsion. They operate with fuel-fired boilers for power generation. In cogenerationapplications requiring both process heat (heat used in an industrial process) and electricity, steam is raised at high pressure in the boiler and extracted from the turbineat th...

• 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...

• World Wide Web.

  browser does not display the URL for the user. Instead, to indicate that an item is selectable, the browser changes the color of the item on the screen and keeps theURL associated with the link hidden. When a user clicks on an item that corresponds to a selectable link, the browser consults the hidden information to find theappropriate URL, which the browser then follows to the selected page. Because a link can point to any page in the Web, the links are known as hyperlinks. See also Hypermedia...

• Computer Memory.

  been created, information can be retrieved but not changed. Newer technologies allow ROMs to be semi-permanent—that is, the information can be changed, but ittakes several seconds to make the change. For example, a FLASH memory acts like a ROM because values remain stored in memory, but the values can be changed. C External Memory External memory can generally be classified as either magnetic or optical, or a combination called magneto-optical. A magnetic storage device, such as a computer'shar...

• Genetic Engineering.

  Pseudomonas fluorescens bacterium. The genetically altered Pseudomonas fluorescens bacterium produces light in proportion to the amount of its activity in breaking down the naphthalene, thus providing a way to monitor the efficiency of the process ( see Bioremediation). A3 Medicine In 1982 the United States Food and Drug Administration (FDA) approved for the first time the medical use of a recombinant DNA protein, the hormone insulin, whichhad been cloned in large quantities by inserting th...

• Business.

  The most common form of ownership is a sole proprietorship —that is, a business owned by one individual. At the beginning of the 21st century, there were more than 17 million sole proprietorships in the United States. These businesses have the advantage of being easy to set up and to dissolve because few laws exist to regulatethem. Proprietors, as owners, also maintain direct control of their businesses and own all their profits. On the other hand, owners of proprietorships are personallyrespon...

• Dog. I 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...

• 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...

• Gardening - biology.

  of synthetic and organic fertilizers, see Organic Farming.) Fertilizers usually are sold in packages, on which the percentage by weight of the macronutrients nitrogen (N), phosphorus (P), and potassium (K) are listed on thelabel—always in the order N-P-K. For example, a fertilizer that is labeled 10-5-3 is 10 percent nitrogen, 5 percent phosphorus, and 3 percent potassium. V PLANTING AND TRANSPLANTING Before planting seeds, gardeners prepare, or till, the soil using a variety of methods. Some...

• Observatory - astronomy.

  Ultraviolet radiation, X rays, and gamma rays have shorter wavelengths than visible light has. These types of radiation tell astronomers about the hottest and mostviolent phenomena in the universe. Earth’s atmosphere blocks most of this radiation, so astronomers must send their observatories above the atmosphere aboardballoons, rockets, or satellites. Ultraviolet telescopes are much like visible light telescopes, but X-ray telescopes must have special nested cylindrical mirrors to prevent Xrays...

• Horse Racing.

  interested parties claim the same horse at the same price, lots are drawn to determine the winning offer. Knowledgeable owners and trainers may use claiming races toobtain, at bargain prices, horses whose former owners underestimated the potential of their animals. Two other types of contests are match races and walkovers. A match race pits only two horses, almost always that season’s most successful racers, in a head-to-headduel. A walkover occurs when only one horse has not been scratched (w...

• Spread of Islam - History.

  Muhammad died in 632 and was succeeded by Abu Bakr, the father of Muhammad’s favorite wife, Aisha. Abu Bakr was the first caliph ( khalifah, Arabic for “successor”) of Islam. Like Muhammad, Abu Bakr was a member of the Quraysh clan. While neither Abu Bakr nor any subsequent caliph claimed the role of prophet, they wereleaders of this new religious enterprise that was quickly becoming a political entity as well. The first four caliphs, all of whom were selected by some form of council ofMuslims,...

• Coral Reef.

  sensitive to particles of mud or sediment settling on them, which means that corals rarely grow close to rivers or other sources of sediment. In the sea, light is filteredout by depth, so reef-building corals can only grow in relatively shallow water. Even in the clearest oceans few reef-building corals grow below a depth of 80 to 100 m(260 to 328 ft). Although corals need nutrients, they cannot thrive in areas where there are large amounts of nutrients. Typically, microscopic organisms in the p...

• Animal Behavior - biology.

  The first motor program analyzed in much detail was the egg-rolling response of geese. When a goose sees an egg outside its nest, it stares at the egg, stretches itsneck until its bill is just on the other side of the egg, and then gently rolls the egg back into the nest. At first glance this seems a thoughtful and intelligent piece ofbehavior, but it is a mechanical motor program; almost any smooth, rounded object (the sign stimulus) will release the response. Furthermore, removal of the egg on...

• Georgia (country) - country.

  1917. During the subsequent Soviet period, religious practice was strongly discouraged because the Soviet state was officially atheistic; however, the GeorgianOrthodox Church was allowed to function openly. Orthodox Christianity is the religion of about 58 percent of the Georgian population. Muslims represent about 19 percent of the country’s population, with ethnicAzerbaijanis, Kurds, and Ajars comprising the principal Muslim groups. Ajars are ethnic Georgians who converted to Islam in the 17th...

• Tennis.

  and interpret rules. The head official on the court, called the chair umpire, sits on a tall chair at one end of the net. A varying number of line judges sit around the courtbeyond the path of the players. Line judges determine whether serves and shots are good or out. A net-cord judge may be employed to determine when a ball touchesthe top of the net, and a foot-fault judge may watch for that specific infraction. In the 1980s electronic devices began to be used in some professional tournaments...