777 résultats pour "where"
-
Cuba - country.
Only two land mammals, the hutia, or cane rat, and the solenodon, a rare insectivore that resembles a rat, are known to be indigenous. The island has numerous batsand nearly 300 kinds of birds, including vultures, wild turkeys, quail, finches, gulls, macaws, parakeets, and hummingbirds. The bee hummingbird of Cuba is thesmallest bird in the world. Among the few reptiles are tortoises, caimans, the Cuban crocodile, and a species of boa that can attain a length of 3.7 m (12 ft). More than700 speci...
-
Arab-Israeli Conflict.
the Suez Canal and in 1951 blockaded the Strait of Tiran (Israel’s access to the Red Sea), which Israel regarded as an act of war. In June 1956 Egypt nationalized theSuez Canal, which had been jointly owned by Britain and France. In late October, Israel invaded the Gaza Strip and Sinai Peninsula, defeating Egyptian forces there.Britain and France attacked Egypt a few days later. Although the fighting was brief and Israel eventually withdrew from the Sinai and Gaza, the conflict furtherexacerbate...
-
Arab-Israeli Conflict - History.
the Suez Canal and in 1951 blockaded the Strait of Tiran (Israel’s access to the Red Sea), which Israel regarded as an act of war. In June 1956 Egypt nationalized theSuez Canal, which had been jointly owned by Britain and France. In late October, Israel invaded the Gaza Strip and Sinai Peninsula, defeating Egyptian forces there.Britain and France attacked Egypt a few days later. Although the fighting was brief and Israel eventually withdrew from the Sinai and Gaza, the conflict furtherexacerbate...
-
Jordan (country) - country.
whom belong to the Greek Orthodox Church, make up about 4 percent of the population. Islam is the state religion and Arabic the official language. C Education Jordan has made significant strides in education in recent decades, despite the influx of hundreds of thousands of refugees and the very large share of the nationalbudget assigned to the armed forces. Public education is free and compulsory between the ages of 6 and 15. At the secondary level, about 85 percent of the malechildren and 87 p...
-
Japan - country.
island’s fertile soils support agriculture and provide the vast majority of Japan’s pasturelands. In addition, Hokkaidō contains coal deposits, and the cold currents off itsshores supply cold-water fish. Winters are long and harsh, so most of Hokkaid ō is lightly settled, housing about 5 percent of Japan’s population on approximately 20 percent of its land area. However,its snowy winters and unspoiled natural beauty attract many skiers and tourists. Hokkaid ō is thought of as Japan’s northern fr...
-
Mexican War.
men, mostly Mexicans, rode to Nacogdoches to capture the rebellious Fredonians. The small garrison of Fredonians soundly defeated their attackers in the only battle ofthe rebellion. When Mexican troops arrived at Nacogdoches a short time later, the republic had been dissolved and the leader of the colonists had fled to Louisiana. B The Texas Revolution Although the Fredonians were not successful, by the 1830s the population of Mexican Texas included many immigrants from the United States. These...
-
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...
-
Automobile Racing.
beginning in 1906 at Le Mans it came to refer to the principal F1 auto race in a given nation, except in the United States, where the term continues to be used lessdiscriminately. After the end of World War I in 1918, when automobile racing blossomed internationally, a series of GP races in several nations became reserved for F1competition, and an annual GP calendar was developed consisting of national races, such as the French Grand Prix and the British Grand Prix. An annual award calledthe Wor...
-
-
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...
-
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...
-
James Monroe.
In October 1786, Monroe resigned from Congress and settled with his bride in Fredericksburg, Virginia, where he began a law practice. His retirement from politics wasbrief. He was soon elected to the town council, and then once again to the Virginia legislature. However, Monroe never lost touch with national politics. He corresponded regularly with both Jefferson and Madison. In 1786 Monroe attended the AnnapolisConvention, which had been called to consider interstate commerce and other matters...
-
James Monroe - USA History.
In October 1786, Monroe resigned from Congress and settled with his bride in Fredericksburg, Virginia, where he began a law practice. His retirement from politics wasbrief. He was soon elected to the town council, and then once again to the Virginia legislature. However, Monroe never lost touch with national politics. He corresponded regularly with both Jefferson and Madison. In 1786 Monroe attended the AnnapolisConvention, which had been called to consider interstate commerce and other matters...
-
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...
-
Philadelphia (city, Pennsylvania) - geography.
national trend of migration from eastern cities to the warmer climate of the Sun Belt. Whereas in 1950 Philadelphia contained more than 2 million people and ranked as the third largest city in America, the city's population plunged to 1,517,550 by 2000.In 2006, the city's population was estimated at 1,448,394. While the city proper was decreasing in population, the metropolitan area centered on Philadelphia grew. In 2006 the region had 6.2 million inhabitants. Philadelphiaranked as the nation’s...
-
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...
-
Madrid - geography.
stores and offices on the first one or two levels. While many people rent their apartments, most own them and participate in cooperatives that maintain the building.Because living spaces are small by American standards, madrileños do most of their socializing in the streets, bars, restaurants, and parks of their neighborhoods. Onlya few very wealthy areas north of the city have single family houses with gardens and yards similar to those in American suburbs. Many of the newest neighborhoodsare c...
-
-
Elementary Particles
I
INTRODUCTION
Structure of Matter
Modern physics has revealed successively deeper layers of structure in ordinary matter.
The most fundamental particles that make up matter fall into the fermion category. These fermions cannot be split into anything smaller. The particles that carry theforces acting on matter and antimatter are bosons called force carriers. Force carriers are also fundamental particles, so they cannot be split into anything smaller.These bosons carry the four basic forces in the universe: the electromagnetic, the gravitational, the strong (force that holds the nuclei of atoms together), and the wea...
-
Civil Rights and Civil Liberties.
A Religious Freedom Although religious freedom has not generally been curtailed in the United States, Roman Catholics, Jews, and members of such unconventional Protestant groups as theOneida Community and the Church of Jesus Christ of Latter-day Saints have historically been discriminated against and sometimes have even been persecuted,although today overt discrimination has almost vanished. The federal Civil Rights Act of 1964, as well as many state and local laws, prohibits religious discrimi...
-
Taxation.
Thus, corporate income faces a higher tax burden than income earned by individuals or by other types of businesses. Tax legislation passed in 2003 in the United Statesattempted to address this issue by lowering the tax rate on dividends. Some economists have proposed abolishing the corporate income tax and instead taxing the owners of corporations (shareholders) through the personal income tax.Other students of the tax system see the corporate income tax as the price corporations pay in return f...
-
Bosnia and Herzegovina - country.
Serb military campaigns in 1992 and 1993 and Croat campaigns in 1993 and 1995 were aimed at expelling others from areas claimed by these groups. By the end ofthe war almost all non-Serbs had been expelled from Serb-claimed lands in eastern and northern Bosnia, and non-Croats from Croat-claimed lands in southwesternBosnia. In turn, most non-Muslims had left land under Muslim control in northwestern Bosnia. The largest cities had mixed populations in 1991, but the war and its aftermath made them a...
-
Memory (psychology).
memory span —how many items people can correctly recall in order. Researchers would show people increasingly long sequences of digits or letters and then ask them to recall as many of the items as they could. In 1956 American psychologist George Miller reviewed many experiments on memory span and concluded that peoplecould hold an average of seven items in short-term memory. He referred to this limit as “the magical number seven, plus or minus two” because the results of thestudies were so consi...
-
Abraham Lincoln
I
INTRODUCTION
Abraham Lincoln (1809-1865), 16th president of the United States (1861-1865) and one of the great leaders in American history.
fence in 4 hectares (10 acres) to grow corn. Then he hired out to neighbors, helping them to split rails. That year, Lincoln attended a political rally and was persuaded tospeak on behalf of a local candidate. It was his first political speech. A witness recalled that Lincoln “was frightened but got warmed up and made the best speech of theday.” In 1831 Lincoln made a second trip to New Orleans. He was hired, along with his stepbrother and a cousin, by Denton Offutt, a Kentucky trader and specul...
-
Abraham Lincoln.
fence in 4 hectares (10 acres) to grow corn. Then he hired out to neighbors, helping them to split rails. That year, Lincoln attended a political rally and was persuaded tospeak on behalf of a local candidate. It was his first political speech. A witness recalled that Lincoln “was frightened but got warmed up and made the best speech of theday.” In 1831 Lincoln made a second trip to New Orleans. He was hired, along with his stepbrother and a cousin, by Denton Offutt, a Kentucky trader and specul...
-
Abraham Lincoln
fence in 4 hectares (10 acres) to grow corn. Then he hired out to neighbors, helping them to split rails. That year, Lincoln attended a political rally and was persuaded tospeak on behalf of a local candidate. It was his first political speech. A witness recalled that Lincoln “was frightened but got warmed up and made the best speech of theday.” In 1831 Lincoln made a second trip to New Orleans. He was hired, along with his stepbrother and a cousin, by Denton Offutt, a Kentucky trader and specul...
-
-
Abraham Lincoln - USA History.
fence in 4 hectares (10 acres) to grow corn. Then he hired out to neighbors, helping them to split rails. That year, Lincoln attended a political rally and was persuaded tospeak on behalf of a local candidate. It was his first political speech. A witness recalled that Lincoln “was frightened but got warmed up and made the best speech of theday.” In 1831 Lincoln made a second trip to New Orleans. He was hired, along with his stepbrother and a cousin, by Denton Offutt, a Kentucky trader and specul...
-
Stone Age.
limestone, quartzite, and indurated shale. Ground stone tools could be made on a wider range of raw material types, including coarser grained rock such as granite. Flaking produces several different types of stone artifacts, which archaeologists look for at prehistoric sites. The parent pieces of rock from which chips have beendetached are called cores, and the chips that have been removed from cores are called flakes. A flake that has had yet smaller flakes removed from one or more edgesin orde...
-
World War I .
and troops to Europe from the United States and other overseas sources. In 1914 Britain implemented a sea blockade of Germany to prevent the delivery of importssuch as food and war materials. The same year, Germany began using submarines to disrupt Allied seaborne traffic and prevent supplies from reaching Britain. In 1915Germany instituted a submarine blockade around Britain. From February 1915 to September 1915 and again in 1917, Germany used unrestricted submarine warfare,sinking ships withou...