Which оf the fоllоwing reаctions is а single displаcement reaction?
Externаl respirаtiоn оccurs between
In his seminаl study, Delinquent Bоys: The Culture оf the Gаng (1955), Albert Cоhen theorized thаt delinquents experience ___________________ because of the disadvantages and inequalities that they face.
Pаssаge 3 | Whо Wаs Genghis Khan? [A] In the 1160s, оn the flоodplains of the Onon River in northeastern Mongolia, a boy named Tamujin was born. As a young man, he organized an alliance of rival tribes among those of the grasslands north of the Gobi desert. Years later, as the fierce warrior-leader Genghis Khan, he led a vast army of nomads out of the grasslands, across deserts, and against societies who had the misfortune to share time and space with the all-powerful Mongols ... [B] 1220. Samarkand, Central Asia. From the city's northwest gate, the inhabitants of Samarkand could only watch in terror as the enormous army approached. Perhaps 80,000 riders could be seen. According to one writer, they appeared "more numerous than ants or locusts, [more than] the sand in the desert, or drops of rain." Before them, the approaching riders drove thousands of captured civilians as a human shield. [C] The city they approached was the capital of Shah Muhammad of the Khwarezm, the center of an empire that included parts of modern-day Afghanistan and Iran. Earlier, the Shah had executed the Mongol ambassador and had sent back the man's head to Genghis Khan, infuriating the Mongol leader. Shah Muhammad had 110,000 troops in the city, but most were poorly disciplined and fled even before the Mongol army arrived. After just a day's fighting, the city gates were opened, and the Shah's people were forced to beg the Mongols for mercy, which they did not receive. [D] Today, there is barely anything left of the once-powerful city of Samarkand. The city was once famed for its copper and silver artisans. An advanced aqueduct system once brought water to the city, making gardens bloom in the dry lands. Today, there is only grass and some occasional bricks. A modern-day Samarkand has grown in its place, but of the original city's great workshops and palaces, nothing remains. [E] The Mongols destroyed every building in the city, killing most of its citizens and taking away many of the survivors to serve as slaves. A city of over 200,000 was erased from the earth. Where the city's mosque once was, archeologist Yuri Buryakov has found the burnt bones of the mosque's defenders. "[T]here were soldiers who did not want to surrender," he says. A thousand withdrew to the mosque, hoping that the Mongols would not kill them there. "But to Mongols it didn't make any difference. They would kill anywhere." [F] Similar stories can be told of other great cities of Central Asia: Bukhara, Balkh, Herat, Ghazni. One after another, they fell to the horsemen who burst from the grasslands of Mongolia. In Afghanistan, even after 750 years, people speak of the Mongol attack as if it happened yesterday. "Only nine!" exclaims one old man in the once elegant city of Herat. "That is all that survived here - nine people!" [G] The name of Genghis Khan brings to mind the most completely ruthless and murderous of history's conquerors. Accounts like that of Samarkand and Herat, rich in poetic exaggeration, seem to be part myth and part history. Experts on 12th-century sources, however, find that some writings need to be critically interpreted to produce a more balanced view of the man and his times. [H] Genghis Khan's love of conquest appears evident in a quotation attributed to him: "Man's greatest good fortune is to chase and defeat his enemy, seize his total possessions, leave his married women weeping ..." In 1215, in the early days of Mongol empire building, Genghis Khan's armies surrounded the city of Zhongdu (modern-day Beijing). Years later, a traveler who noticed a white hill was told it was the bones of Zhongdu's inhabitants. It is said that even on his death bed, Genghis Khan ordered the killing of the entire population of Xi Xia, a neighboring state that had defied him. [I] Yet the reputation of Genghis Khan as an utterly ruthless warrior may be worse than the reality. Much of our information comes from chroniclers of the time who often exaggerated the facts. It is possible they were encouraged by their Mongol employers to exaggerate the tales of cruelty so that the Mongols appeared more frightening to their enemies. In the city of Nishapur, a chronicler wrote that the Mongols were brutal to the extent that even the city's dogs and cats were killed. "There's no question that there was a great deal of destruction," says Mongol expert Morris Rossabi. "[But] not all the cities were butchered." The Secret History of the Mongols, an account of Genghis Khan's early life and the oldest surviving literary work in the Mongolian language, may also have bent the truth so as to enhance his reputation. "It is full of myths and legends," says historian Larry Moses, although "some of it can be [supported by] Chinese sources." [J] In his homeland, Genghis Khan's reputation needs little enhancement. There he is revered as the first ruler of a united Mongolia, and his face can be found on paper currency. Mongolian historian Shirendev Bagaryn interprets Genghis Khan's conquests in a more positive light: "When you are eating," he says, "your appetite grows. Once you are strong you want to go find out how other people live ... He needed their knowledge to develop his country" - for example, by borrowing the written script that his neighbors used in western China. Other historians believe that Genghis was driven less by a thirst for land than by a need to feed his people: "I don't think he consciously set out to be a conqueror," says Rossabi. "In general, he didn't try to hold on to territory, except for Mongolia." [K] At the age of about 60, after conquering much of continental Asia, Genghis Khan died, possibly after falling from his horse. His body was taken back to Mongolia for burial. Of his grave, like much of the societies he conquered, nothing remains. According to one Persian historian, Genghis Khan was "possessed of great energy ... a genius ... a butcher, just, resolute ... and cruel," which might serve as a fair epitaph. It is true that the Mongols under Genghis Khan committed ruthless acts, killing armies as well as peaceful citizens and forcing millions to accept their rule. But the 13th century saw many wars where cruelty was the norm. It could be argued that Genghis Khan was simply a man of his time, a man who happened to be a brilliant military leader, and who gave to his descendants the greatest empire - and the most powerful army - the world had ever seen. Passage 3 | Question 2 What motivated Genghis Khan to attack Samarkand?
Pаssаge 2 | Spirits in the Sаnd Recent findings shed light оn the lives - and mysteriоus disappearance - оf the ancient Nasca. [A] Since their mysterious desert drawings became widely known in the late 1920s, the people known as the Nasca have puzzled archeologists, anthropologists,1 and anyone else who is fascinated by ancient cultures. Their elaborate lines and figures, called geoglyphs, are found distributed, seemingly at random, across the desert outside Nasca and the nearby town of Palpa. Waves of scientists - and amateurs - have come up with various interpretations for the designs. At one time or another, they have been explained as Inca roads, irrigation plans, and even, controversially, landing strips for alien spacecraft. [B] Since 1997, an ongoing Peruvian-German research collaboration called the Nasca-Palpa Project has been putting these theories to the test. The leaders of the project are Johny Isla and Markus Reindel of the German Archaeological Institute. As well as studying where and how the Nasca lived, the researchers have investigated why they disappeared and the meaning of the strange, abstract designs they left behind. If Isla and his colleagues are right, the story of Nasca begins and ends, with water. Living on the Edge [C] The coastal region of southern Peru and northern Chile is one of the driest places on Earth. In the small, protected basin where the Nasca culture arose, ten rivers descend from the Andes. Most of these rivers are dry at least part of the year. Surrounded by a thousand shades of brown, these ten ribbons of green offered a fertile spot for the emergence of early civilization. "It was the perfect place for human settlement because it had water," says geographer Bernhard Eitel, a member of the Nasca-Palpa Project. "But it was a very high-risk environment." [D] According to Eitel and his colleague Bertil Machtle, the micro-climate in the Nasca region has undergone considerable variation over the past 5,000 years. When a high-pressure system over central South America called the Bolivian High moves to the north, more rain falls on the western slopes of the Andes. When the high shifts southward, precipitation decreases. This causes the rivers in the Nasca valleys to run dry. [E] Despite the risky conditions, the Nasca lived in the area for eight centuries following their appearance in about 300 B.C. As the rainfall cycle continued, people moved east or west along the river valleys. In the arid southern valleys, early Nasca engineers devised practical ways of coping with the scarcity of water. An ingenious system of horizontal wells tapped into the inclined water table as it descended from the Andean foothills. These irrigation systems, or puquios, allowed the Nasca to bring subterranean2 water to the surface. [F] The Nasca people were in fact remarkably "green," perhaps because of the environmental challenges they faced. The creation of the puquios displayed a sophisticated sense of water conservation since the underground aqueducts3 minimized evaporation. The farmers planted seeds by making a single hole in the ground rather than plowing, thereby preserving the substructure of the soil. The Nasca also recycled their garbage as a building material. "It's a society that managed its resources very well," says Isla. "This is what Nasca is all about." Praying for Water [G] For centuries, Andean people have worshipped the gods of mountains that feed the Nasca drainage system. According to National Geographic explorer Johan Reinhard, the Nasca has traditionally associated these mountains - mythologically, if not geologically - with water. Evidence for Reinhard's thesis came in 1986, when he found the ruins of a ceremonial stone circle at the summit of Illakata, one of the region's tallest mountains. Reinhard believes the Nasca lines were most likely related to the worship of mountain gods, because of their connection to water. [H] Further evidence connecting Nasca rituals to water worship was revealed by the Nasca-Palpa Project researchers in 2000. On a plateau4 near the village of Yunama, Markus Reindel made an important discovery. As he was excavating a mound, he uncovered several broken pots and other relics that clearly represented ritual offerings. Then he came upon pieces of a large seashell. It was of a genus5 called Spondylus. [I] "The Spondylus shell is one of the few items of Andean archeology that has been well studied," Reindel says. "It's a very important religious symbol for water and fertility ... It was brought from far away and is found in specific contexts, such as funerary objects and on these platforms. It was connected in certain activities to praying for water. And it's clear in this area, water was the key issue." [J] In 2004, archeologist Christina Conlee made a much grimmer discovery. Conlee was working at a site near a dry river valley in the southern Nasca region. While excavating a Nasca tomb, she unearthed a skeleton. However, the first part to emerge from the dirt was not the skull, but the neck bones. "We could see the vertebrae6 sitting on top," Conlee says. "The person was seated, with arms crossed and legs crossed, and no head." Cut marks on the neck bones indicate the head had probably been severed by a sharp knife. A ceramic pot known as a head jar rested against the elbow of the skeleton. An illustration on the jar showed a decapitated7 "trophy head." Out of the head grew a strange tree trunk with eyes. [K] Everything about the burial - the head jar, the placement, and position of the body - suggests the body was disposed of in a careful manner. Conlee suspects the skeleton represents a ritual sacrifice. "Although we find trophy heads spread throughout the Nasca period," she said, "there are some indications that they became more common in the middle and late period, and also at times of great environmental stress, perhaps drought. If this was a sacrifice, it was made to appease8 the gods, perhaps because of a drought or crop failure." Beginning of the End [L] Despite their offerings, the Nasca's prayers would ultimately go unanswered. Water - or more precisely, its absence - was increasingly critical in the Nasca's final years, between about A.D. 500 and A.D. 600. [M] In the Palpa area, scientists have traced the movement of the eastern margin of the desert about 19 kilometers (12 miles) up the valleys between 200 B.C. and A.D. 600. At one point, the desert reached an altitude of over 1,900 meters (6,500 feet). Similarly, the population centers around Palpa moved farther up the valleys, as if they were trying to outrun the arid conditions. "At the end of the sixth century A.D.," Eitel and Machtle conclude in a recent paper, "the aridity culminated9 and the Nasca society collapsed." [N] Nevertheless, environmental stresses were not the only vital factor. "It wasn't just climate conditions that caused the collapse of Nasca culture," emphasizes Johny Isla. "A state of crisis was provoked10 because water was more prevalent in some valleys than in others, and the leaders of different valleys may have been in conflict." By about A.D. 650, the more militaristic Wari (Huari) Empire had emerged from the central highlands and displaced the Nasca as the predominant culture in the southern desert region. [O] Almost 1,500 years later, the legacy of the Nasca lives on. You can see it in the artifacts11 of their ancient rituals, in the remains of their irrigation systems, and - most famously - in the lines of their mysterious desert designs. The lines surely provided a ritualistic reminder to the Nasca people that their fate was intrinsically tied to their environment. In particular, the lines represent a bond with the Nasca's most precious resource, water. You can still read their reverence for nature, in times of plenty and in times of desperate want, in every line and curve they scratched onto the desert floor. And when your feet inhabit their sacred space, even for a brief and humbling moment, you can feel it. Passage 2 | Question 7 What is a Spondylus?
Pаssаge 1 | Humаn Biоnics [A] Amanda Kitts is mоbbed by fоur- and five-year-olds as she enters the classroom. "Hey, kids, how're my babies today?" she says, patting shoulders and ruffling1 hair. Slender and energetic, she has operated this Knoxville, Tennessee, daycare center and two others for almost 20 years. She crouches down to talk to a small girl, putting her hands on her knees. [B] "The robot arm!" several kids cry. "You remember this, huh?" says Kitts, holding out her left arm. As she turns her hand palm up, there is a soft whirring sound. If you weren't paying close attention, you'd miss it. She bends her elbow, accompanied by more whirring. [C] "Make it do something silly!" one girl says. "Silly? Remember how I can shake your hand?" Kitts says, extending her arm and rotating her wrist. A boy reaches out, hesitantly, to touch her fingers. What he brushes against is flesh-colored plastic, fingers curved slightly inward. Underneath are three motors, a metal framework, and a network of sophisticated electronics. The assembly is topped by a white plastic cup midway up Kitts's biceps, encircling a stump2 that is almost all that remains from the arm she lost in a car accident in 2006. [D] Almost all, but not quite. Within her brain, below the level of consciousness, lives an intact image of that arm, a phantom. When Kitts thinks about flexing3 her elbow, the phantom moves. Impulses racing down from her brain are picked up by electrode sensors in the white cup and converted into signals that turn motors, and the artificial elbow bends. [E] "I don't really think about it. I just move it," says Kitts, who uses both this standard model and a more experimental arm with even more control. "After my accident, I felt lost. These days I'm just excited all the time, because they keep on improving the arm. One day I'll be able to feel things with it and clap my hands together in time to the songs my kids are singing." [F] Kitts is one of "tomorrow's people," a group whose missing or ruined body parts are being replaced by devices embedded in their nervous systems that respond to commands from their brains. The machines they use are called neural prostheses or - using a term made popular by science fiction writers - bionics. [G] The kind of prosthesis that Amanda Kitts uses is controlled by her brain. A technique called targeted muscle reinnervation uses nerves remaining after an amputation4 to control an artificial limb. It was first tried in a patient in 2002. Four years later, Tommy Kitts, Amanda's husband, read about the research, which took place at the Rehabilitation Institute of Chicago (RIC). His wife lay in the hospital at the time; the truck that had crushed her car had also crushed her arm, from just above the elbow down. [H] "I was angry, sad, depressed; I just couldn't accept it," she says. But the news Tommy brought her about the Chicago arm gave her some reassurance, and some hope. "It seemed like the best option out there, a lot better than motors and switches," Tommy says. "Amanda actually got excited about it." Soon they were on a plane to Illinois. [I] Todd Kuiken, a licensed medical practitioner and biomedical engineer at RIC, was the person responsible for what the institute had begun calling the "bionic arm." He knew that nerves in an amputee's stump could still carry signals from the brain, and he knew that a computer in a prosthesis could direct electric motors to move the limb. However, making the connection was far from straightforward. Nerves conduct electricity, but they can't be spliced together with a computer cable. (Nerve fibers and metal wires are not mutually compatible, and an open wound where a wire enters the body would be a dangerous avenue for infections.) [J] Kuiken needed an amplifier to boost the signals from the nerves, avoiding the need for a direct contact between nerve and wire. He found one in muscles. When muscles tense, they give off an electrical burst strong enough to be detected by an electrode placed on the skin. He developed a technique to reroute severed nerves from their old, damaged spots to other muscles that could give their signals the proper boost. [K] In October 2006, Kitts consented to have Kuiken try out his new technique on her. The first step was to salvage major nerves that once went all the way down her arm. "These are the same nerves that work the arm and hand, but we had to create four different muscle areas to lead them to," Kuiken says. The nerves started in Kitts's brain - in the motor cortex, which holds a rough map of the body - but they terminated at the end of her stump. In an intricate operation, a surgeon rerouted those nerves to different regions of Kitts's upper-arm muscles. For months the nerves grew, millimeter by millimeter, moving deeper into their newly assigned homes. [L] "At three months, I started feeling little tingles and twitches," says Kitts, "and by four months, I could actually feel different parts of my hand when I touched my upper arm. I could touch it in different places and feel different fingers." What she was feeling were parts of the phantom arm that were mapped into her brain, now reconnected to flesh. When Kitts thought about moving those phantom fingers, her real upper-arm muscles contracted. [M] A month later, she was fitted with her first bionic arm, which had electrodes in the cup around the stump to pick up the signals from the muscles. Now the challenge was to convert those signals into commands to adjust the elbow and hand. A storm of electrical noise was coming from the small region on Kitts's arm. Somewhere in there was the signal that meant "straighten the elbow" or "turn the wrist." A microprocessor inserted in the prosthesis had to be programmed to differentiate the right signal and send it to the right motor. [N] Kitts practiced using her arm one floor below Kuiken's office in an apartment set up by occupational therapists. The apartment had a kitchen with a stove, silverware in a drawer, a bed, a closet with hangers, a bathroom, and stairs - things people use every day without a second thought but that pose huge obstacles to someone missing a limb. [O] Watching Kitts make a peanut butter sandwich in the kitchen is a startling experience. With her sleeve rolled back to reveal the plastic cup, her motion is fluid. Her live arm holds a slice of bread, her artificial fingers close on a knife, the elbow flexes, and she swipes peanut butter back and forth. "It wasn't easy at first," she says. "I would try to move it, and it wouldn't always go where I wanted." But she worked at it, and the more she used the arm, the more lifelike the motions felt. [P] What Kitts would really like now is sensation. That would be a big help in many actions, including one of her favorites - gulping coffee. "The problem with a paper coffee cup is that my hand will close until it gets a solid grip. But with a paper cup, you never get a solid grip," she says. "That happened at Starbucks once. It kept squeezing until the cup went ‘pop.'" [Q] There are valid reasons for supposing that one day she'll get that sensation, says Kuiken. In partnership with bioengineers at the Johns Hopkins University Applied Physics Laboratory, RIC has been developing a new prototype5 for Kitts and other patients that not only has more flexibility - more motors and joints - but also has pressure-sensing pads on the fingertips. The pads are connected to small rods that poke into Kitts's stump. The harder the pressure, the stronger the sensation in her phantom fingers. [R] "I can feel how hard I'm grabbing," she says. She can also differentiate between rubbing something rough, like sandpaper, and smooth, like glass, by how fast the rods vibrate. "I go up to Chicago to experiment with it, and I love it," she says. "I want them to give it to me already so I can take it home. But it's a lot more complicated than my take-home arm, so they don't have it completely reliable yet." [S] Today, Kitts has a new, more elastic cup atop her arm that better aligns electrodes with nerves that control the arm. "It means I can do a lot more with the arm," she says. "A new one up in Chicago lets me do lots of different hand grasps - I want that. I want to pick up pennies and hammers and toys with my kids." These are reasonable hopes for a substitute body part, Kuiken says. "We are giving people tools, and they are better than what previously existed. But they are still crude, like a hammer, compared with the complexity of the human body." [T] The work of neural prostheses is extremely delicate, a series of trials filled with many errors. As scientists have learned that it's possible to link machine and mind, they have also learned how difficult it is to maintain that bond. Still, bionics represents a major leap forward, enabling researchers to give people back much more of what they've lost than was ever possible before [U] "That's really what this work is about: restoration," says Joseph Pancrazio, program director for neural engineering at the National Institute of Neurological Disorders and Stroke. "When a person with a spinal cord injury can be in a restaurant, feeding himself, and no one else notices, that is my definition of success." Passage 1 | Question 9 Which of the following statements is a fact, NOT an opinion?
Vоcаbulаry | Unit 11B аmend empirical integrity liberal splendid appendage initiated invоked persecutiоn violate DIRECTIONS: Match each vocabulary word with the CAPITALIZED word or phrase that best demonstrates its meaning.