Narrator Listen to part of a lecture in a biology class. Now get ready to answer the questions. You may use your notes to help you answer.

TORNADO FORMATION 1 Tornadoes are one of the most violent of all weather systems. A tornado can produce tremendous destructive power in a restricted area as it passes by, sweeping the ground clear of all movable objects. Fortunately, tornadoes are short-lived and often strike sparsely populated regions. Occasionally, however, a major tornado outbreak causes incredible devastation. A tornado's powerful blasts of wind put all human life in jeopardy, sending debris flying and lifting buildings from their foundations. 2 The formation of tornadoes has been the subject of increasingly fruitful research. {{U}}Nevertheless, some mystery still surrounds tornadoes, and their formation cannot be predicted with absolute accuracy, even when conditions for their occurrence seem just right.{{/U}} Most tornadoes are created by, and travel with, intense thunderstorm cells. Because tornadoes require moist air, they favor the warmest part of the day, when solar heating and thunderstorm development are at their maximum. 3 Probably the most striking characteristic of a tornado is its spinning funnel cloud, a lowering of cloud base into a column that narrows as it reaches down to the ground from a parent cloud that is part of an active thunderstorm. The funnel cloud forms in response to the steep air pressure directed from the storm's outer edge toward its center. Humid air expands and cools as it is drawn inward toward the center of the system. The cooling of air below its dewpoint causes water vapor to condense into cloud droplets. 4 The actual tornadic circulation covers a much wider area than the funnel cloud suggests. The funnel may range in diameter from a few meters to 3.2 kilometers (2 miles). However, the diameter of a funnel cloud is typically only about one-tenth that of the associated tornadic circulation. Several funnels may develop in a {{U}}mature{{/U}} tornado system, with small vortexes continually forming and then disappearing while {{U}}whirling{{/U}} around the central core of the main tornado. The funnels may be made visible by the presence of dust and debris. A funnel can assume a variety of forms, from a thin, writhing, ropelike pendant of grayish white to a thick mass of menacing black. 5 The central United States is one of only a few places in the world where the spring weather conditions and flat terrain are ideal for tornado development. Although tornadoes have been reported in all 50 states and throughout southern Canada, most occur in "tornado alley," a level corridor that stretches from eastern Texas northward through the open plains of Oklahoma, Kansas, and Nebraska. 6 Almost three-quarters of the tornadoes in North America occur from March to July. The months of peak {{U}}tornado activity{{/U}} are April (13%), May (12%), and June (21%). During that time of year, weather conditions are optimal for causing the severe thunderstorms that produce tornadoes. One contributing factor is the relative instability of the lower atmosphere. During the transition from winter to summer, days lengthen, thereby warming the ground. Heat is transferred from the ground into the troposphere, but it takes time for the entire troposphere to adjust to receiving heat from below. The upper troposphere, in fact, usually retains its winter cold into the spring months. The result is an imbalance of cold air and warm ground that favors the development of rotating thunderstorms known as supercells. 7 In the Northern Hemisphere, tornadoes almost always spin counterclockwise. Around 87 percent of all tornadoes and their parent cells travel from southwest to northeast, but any direction is possible. Tornado trajectories are often irregular, with many tornadoes exhibiting a {{U}}hopscotch{{/U}} pattern of destruction as they alternately touch down and lift off the ground. Some have been known to move in {{U}}circles{{/U}} and even to describe {{U}}figure eights{{/U}}. Tornadoes may track along paths from several meters to more than 320 kilometers (200 miles) long. Average forward speed is around 48 kilometers (30 miles) per hour, although there are reports of tornadoes racing along at speeds approaching 120 kilometers (75 miles) per hour. During part of its course, the great Tri-State Tornado on March 18, 1925, moved at the astonishing rate of 117 kilometers (73 miles) per hour, killing 695 people in Missouri, Illinois, and Indiana, and making it one of the most deadly tomadoes on record.

Reading3"LifeinOurSolarSystem"Althoughwecanimaginelifebasedonsomethingotherthancarbonchemistry,weknowofnoexamplestotellushowsuchlifemightariseandsurvive.Wemustlimitourdiscussiontolifeasweknowitandtheconditionsitrequires.Themostimportantrequirementisthepresenceofliquidwater,notonlyaspartofthechemicalreactionsoflife,butalsoasamediumtotransportnutrientsandwasteswithintheorganism.Thewaterrequirement{{U}}automatically{{/U}}eliminatesmanyworldsinoursolarsystem.Themoonisairless,andalthoughsomedatasuggesticefrozeninthesoilatitspoles,ithasneverhadliquidwateronitssurface.Inthevacuumofthelunarsurface,liquidwaterwouldboilawayrapidly.Mercurytooisairlessandcannothavehadliquidwateronitssurfaceforlongperiodsoftime.Venushassometracesofwatervaporinitsatmosphere,butitismuchtoohotforliquidwatertosurvive.Iftherewereanylakesoroceansofwateronitssurfacewhenitwasyoung,theymusthaveevaporatedquickly.Eveniflifebeganthere,notraceswouldbeleftnow.Theinnersolarsystemseemstoohot,andtheoutersolarsystemseemstoocold.TheJovianplanetshavedeepatmospheres,andatacertainlevel,theyhavemoderatetemperatureswherewatermightcondenseintoliquiddroplets.Butitseemsunlikelythatlifecouldbeginthere.TheJovianplanetshavenosurfaceswhereoceanscouldnurturethebeginningoflife,andcurrentsintheatmosphereseemdestinedtocirculategasandwaterdropletsfromregionsofmoderatetemperaturetootherlevelsthataremuchtoohotortoocoldforlifetosurvive.AfewofthesatellitesoftheJovianplanetsmighthavesuitableconditionsforlife.Jupiter'smoonEuropaseemstohavealiquid-wateroceanbelowitsicycrust,andmineralsdissolvedinthatwaterwouldprovidearichbrothofpossi-bilitiesforchemicalevolution.Nevertheless,Europaisnotapromisingsitetosearchforlifebecauseconditionsmaynothaveremained{{U}}stable{{/U}}forthebillionsofyearsneededforlifetoevolvebeyondthemicroscopicstage.IfJupiter'smoonsinteractgravitationallyandmodifytheirorbits,Europamayhavebeenfrozensolidatsomepointsinhistory.→Saturn'smoonTitanhasanatmosphereofnitrogen,argon,andmethaneandmayhaveoceansofliquidmethaneandethaneonitssurface.Thechemistryoflifethatmightcrawlorswimonsuchaworldisunknown,butlifetheremaybeunlikelybecauseofthetemperature.ThesurfaceofTitanisadeadly-179℃(-290°F).Chemicalreactionsoccurslowlyornotatallatsuchlowtemperatures,sothechemicalevolutionneededtobeginlifemayneverhaveoccurredonTitan.→Marsisthemostlikelyplaceforlifeinoursolarsystem.Theevidence,however,isnotencouraging.MeteoriteALH84001wasfoundontheAntarcticicein1984.ItwasprobablypartofdebrisejectedintospacebyalargeimpactonMars.ALH84001isimportantbecauseateamofscientistsstudieditandannouncedin1996thatitcontainedchemicalandphysicaltracesofancientlifeonMars.Scientistswereexcitedtoo,butbeingprofessionallyskeptical,theybegantestingtheresultsimmediately.{{U}}Inmanycases,theresultsdidnotconfirmthe{{/U}}{{U}}conclusionthatlifeonceexisted0nMars.{{/U}}SomechemicalcontaminationfromwateronEarthhasoccurred,andsomechemicalsinthemeteoritemayhave{{U}}originated{{/U}}withoutthepresenceoflife.Thephysicalfeaturesthatlooklikefossilbacteriamaybemineralformationsintherock.SpacecraftnowvisitingMarsmayhelpusunderstandthepasthistoryofwaterthereandpaintamoredetailedpictureofpresentconditions.Nevertheless,conclusiveevidencemayhavetowaituntilageologistinaspacesuitcanwanderthedrystreambedsofMarscrackingopenrocksandsearchingforfossils.Wearelefttoconcludethat,sofarasweknow,oursolarsystemisbareoflifeexceptforEarth.Consequently,oursearchforlifeintheuniversetakesustootherplanetarysystems.

European History: Ireland Famine Professor: When you hear the word famine today, you think of Africa and starving millions ______. But a hundred and fifty years ago, Ireland, the Emerald Isle next to England, ______. And like today"s story of starvation the reasons for the famine are the same: ______, politics and natural disaster. Ireland in 1845, the time of the Great Famine, was a country in big change ______ the industrial revolution and a ballooning population. In the beginning of the 18th century there were some four and a half million Irish. Fifty years, or two generations later, that number had ______. Most of the population were Roman Catholic, poor and worked on small farms ______. There was no ______ and families with 10 or 12 children were not uncommon. ______ there was never much food to go around. It didn"t matter if you lived in the country or in the shadow of factory smokestacks in ______. Life was a struggle. Think of the world of Charles Dickens and his poor, workhouse boys, Oliver Twist and David Copperfield, begging for food, ______. The main food in Ireland was the white potato, known today as the Irish potato. This wonder crop, which was cheap to grow and plentiful when ______, was one of the reasons there ever was an industrial revolution in Europe. When the Spanish explorers brought the potato ______ to Europe around 1550, they changed the whole diet of Europe. By 1800, the Irish were totally dependent on the potato as their primary food and cash crop for export. When ______ in the fall of 1845, half the harvest was lost. The next year the crop also failed. The poor Irish tenants ______ or feed their families. They were dying of starvation and disease, and yet their greedy English landlords continued to ______ to England to make bread, and to feed the poor farmers and workers they imported cheap meal from India. In addition to being a ______ basic food, the cheap meal ______. The majority of Irish famine victims died from malnutrition diseases such as ______, rather than directly from starvation. The famine is only one of the many nails ______ that exists between the Irish and the English today. Ireland remains partitioned with Northern Ireland still a part of the United Kingdom, because of religious differences, but also because of such ______ that led to the Great Famine and one of the biggest waves of emigration. The only choice many Irish had was to ______. Under the Passenger Act of 1847 more than a million and a half Irish immigrated to Canada and the U.S. ______ for the New World ______ 10 cubic feet, the size of a single bed, and a supply of food and water. Most ships" captains ______ and almost half of the passengers died in these coffin ships. They had different skin color from the African slaves, but the same inhumane conditions. Sadly history repeats itself. And it appears famine will be with us ______ other men and use food as a weapon.

LISTENING SECTION DIRECTIONS The Listening section measures your ability to understand conversations and lectures in English. You will near each conversation and lecture only one time. After each conversation or lecture, you will hear some questions about it. Answer the questions based on what the speakers state or imply. You may take notes while you listen. You may use your notes to help you answer the questions. In some questions, you will see this icon: This means that you will hear, but not see, part of the question. Some questions have special directions, which appear in a gray box. Most questions are worth one point. If a question is worth more than one point, the directions will indicate how many points you can receive. You will now begin the first part of the Listening section. {{B}}Set 1 Conversation{{/B}}

Dorothy Crowfoot Hodgkin When Dorothy Crowfoot Hodgkin was ten years old, she watched her first crystals form on a string dangling in a glass of salt water. Many children before and since have done the same, but in Hodgkin's case, the sparkling geometric shapes {{U}}kindled{{/U}} a fascination that would lead her to world fame. In 1964, nearly half a century later, Hodgkin received a Nobel Prize in Chemistry for discovering the structures of penicillin and vitamin B12 from photographic images of their crystals. She made the images with a technique called x-ray crystallography, which involves firing x-rays through a crystal to determine the arrangement of the atoms in it. It is a bit like determining the shape of a jungle gym from its shadow. Born in 1910, Hodgkin spent the first few years of her life in Cairo, where her father was an official in the British colonial government. Most of her education had been at home, but once back at school in England, her keen interest in crystals won the attention of her schoolteacher. Hodgkin and a friend got special permission to join the boys studying chemistry. By age 12, she was doing chemistry experiments on rocks she found in her garden to see what they contained. That summer, while visiting her father in Khartoum, Sudan, she met Dr. A. E. Joseph, a friend of her father's and a well-known soil chemist. Joseph took her on a tour of his laboratory. Pleased by her intense interest, he put together a small chemistry set for her, which she took back to England and set up in her mother's attic. It was her first laboratory. Hodgkin enrolled at Oxford University, where she eventually specialized in x-ray crystallography. At the time, the analysis of the structures of even the simplest chemicals by x-ray crystallography required at least 30 sets of calculations, all done by hand. The work {{U}}demanded{{/U}} perseverance and diligence, and a good head for math. Under these conditions, Hodgkin flourished. Seeking a greater challenge after college, Hodgkin went to Cambridge to study with a young crystallographer named J.D. Bernal. Together they solved some of the most complex chemical structures ever attempted, including {{U}}those{{/U}} of several vitamins and sex hormones. They took the first x-ray photographs of a protein—the stomach enzyme pepsin—showing that proteins form regular crystals. In 1937, Hodgkin received her doctorate. Within a few months, she also married historian Thomas Hodgkin, taking his name. The Hodgkins were a two-career family, working in different towns and {{U}}commuting{{/U}} on alternate weekends to see each other. Dorothy Hodgkin remained at Oxford, where she continued her research, taught university classes, and raised three children. When the demand for penicillin soared during World War Ⅱ, chemists all over the world raced to determine its structure. Experimental chemists used chemical reactions. Structural chemists, such as Hodgkin, used crystallography. Despite daunting calculations, Hodgkin and her students at Oxford completed the structure in 1949, beating the experimental chemists and establishing x-ray crystallography as an indispensable tool in biochemistry. Even as Hodgkin was finishing her analysis of penicillin, however, she had already begun a study of B12, widely used to treat pernicious anemia. In 1957, she published the structure of this 180-atom molecule. A. [■] When she was awarded the Nobel Prize in 1964, she told a group of students at the ceremonies in Stockholm, Sweden, that she hoped her position as the only woman to receive the prize that year "will not be so very uncommon in the future, as more and more women carry out research in the same way as men". B. [■] But what was perhaps Hodgkin's greatest success came after the Nobel Prize, when she tackled the biggest molecule of her career. Insulin, a protein that regulates the body's sugar storage, contains over 1000 atoms.C. [■] A deficiency in or insensitivity to insulin causes diabetes, a complex disease that causes suffering in several hundred million people worldwide. Hodgkin solved the structure of insulin in only five years. D. [■] Her achievement proved that proteins have regular shapes, and it spawned research that ultimately led to effective treatments for diabetes.

Directions: Read the passage. Then answer the questions. Give yourself 20 minutes to complete this practice set. PETROLEUM RESOURCES Petroleum, consisting of crude oil and natural gas, seems to originate from organic matter in marine sediment. Microscopic organisms settle to the seafloor and accumulate in marine mud. The organic matter may partially decompose, using up the dissolved oxygen in the sediment. As soon as the oxygen is gone, decay stops and the remaining organic matter is preserved. Continued sedimentation—the process of deposits' settling on the sea bottom—buries the organic matter and subjects it to higher temperatures and pressures, which convert the organic matter to oil and gas. As muddy sediments are pressed together, the gas and small droplets of oil may be squeezed out of the mud and may move into sandy layers nearby. Over long periods of time (millions of years), accumulations of gas and oil can collect in the sandy layers. Both oil and gas are less dense than water, so they generally tend to rise upward through water-saturated rock and sediment. Oil pools are valuable underground accumulations of oil, and oil fields are regions underlain by one or more oil pools. When an oil pool or field has been discovered, wells are drilled into the ground. Permanent towers, called derricks, used to be built to handle the long sections of drilling pipe. Now portable drilling machines are set up and are then dismantled and removed. When the well reaches a pool, oil usually rises up the well because of its density difference with water beneath it or because of the pressure of expanding gas trapped above it. Although this rise of oil is almost always carefully controlled today, spouts of oil, or gushers, were common in the past. Gas pressure gradually dies out, and oil is pumped from the well. Water or steam may be pumped down adjacent wells to help push the oil out. At a refinery, the crude oil from underground is separated into natural gas, gasoline, kerosene, and various oils. Petrochemicals such as dyes, fertilizer, and plastic are also manufactured from the petroleum. As oil becomes increasingly difficult to find, the search for it is extended into more-hostile environments. The development of the oil field on the North Slope of Alaska and the construction of the Alaska pipeline are examples of the great expense and difficulty involved in new oil discoveries. Offshore drilling platforms extend the search for oil to the ocean's continental shelves—those gently sloping submarine regions at the edges of the continents. More than one-quarter of the world's oil and almost one-fifth of the world's natural gas come from offshore, even though offshore drilling is six to seven times more expensive than drilling on land. A significant part of this oil and gas comes from under the North Sea between Great Britain and Norway. Of course, there is far more oil underground than can be recovered. It may be in a pool too small or too far from a potential market to justify the expense of drilling. Some oil lies under regions where drilling is forbidden, such as national parks or other public lands. Even given the best extraction techniques, only about 30 to 4.0 percent of the oil in a given pool can be brought to the surface. The rest is far too difficult to extract and has to remain underground. Moreover, getting petroleum out of the ground and from under the sea and to the consumer can create environmental problems anywhere along the line. Pipelines carrying oil can be broken by faults or landslides, causing serious oil spills. Spillage from huge oil-carrying cargo ships, called tankers, involved in collisions or accidental groundings can create oil slicks at sea. Offshore platforms may also lose oil, creating oil slicks that drift ashore and foul the beaches, harming the environment. Sometimes, the ground at an oil field may subside as oil is removed. The Wilmington field near Long Beach, California, has subsided nine meters in 50 years; protective barriers have had to be built to prevent seawater from flooding the area. Finally, the refining and burning of petroleum and its products can cause air pollution. Advancing technology and strict laws, however, are helping control some of these adverse environmental effects.

Work Study Program Advisor: Hi, Sue. How can I help you? Student: Hi, Jack, I"m interested in the work study program ______. I am a senior student. Can you tell me some of the advantages of the program? Advisor: Well, you get paid a salary so you ______. You ______ practical experience through working with professionals who can ______. It is a good way to learn what your strengths and weaknesses are. It also looks ______ if you have actual work experience. Student: How do I know if there is a work study position ______? Advisor: What is your major? Student: Business Administration. Advisor: Excellent. There are lots of opportunities to work in offices in accounting. If you fill in the work study application and get two of your instructors to send ______ directly to the Student Employment Office, Room 510 Sedgewick Hall, we can ______. If it is approved, we will arrange a further interview with you to determine your skills and exactly what you want to do. We then arrange interviews with employers, but we ______. Student: Can I pick which company I want to work at? Advisor: There is a place on the application for you to list three companies that you are interested in, but there are absolutely no guarantees ______. At certain times of the year, some employers are too busy to train, or they have no space, or they just don"t want to bother with students. Student: What are the chances of ______? Advisor: About 40～50%. Student: How much will I be paid? Advisor: The employer must ______ with the same education and experience as you. The salaries ______. Student: Will I just be filing, or will I get to do some accounting too? Advisor: The employer provides a job description ______. The supervisor will give you an orientation, provide you with a desk and give you appropriate work ______. Student: What if I don"t like it there? Advisor: Two weeks after the placement, our work study coordinator will visit you and your supervisor to evaluate the situation. If either of you are unhappy at that time, ______ together. If they cannot be resolved，______ we would try to find another placement for you. Student: How am I evaluated? Advisor: The supervisor assigned to you does three evaluations. We provide him with the forms. The first evaluation is done after two weeks, the second after six weeks, and the final one ______. Student: How long is the placement? Advisor: It is one full term—usually about four months. Student: Can I choose my own hours? Advisor: Absolutely not. You must ______. It is very important you ______. You are representing this college in the placement and you are ______ professionally. It is also very important that you keep all company information confidential. That is especially important in your field, as I am sure you already know. Student: How many students are ______ from their work study placement? Advisor: That varies with the economy, the specialty of the student and other factors. Generally though, over 70% of our placements ______ after graduation. Student: Could I please have an application? Advisor: If there is anything else I can help you with, just give me a call. Student: Thank you very much.

Reading1"LayersofSocialClass"Takentogether,income,occupation,andeducationaregoodmeasuresofpeople'ssocialstanding.Usingalayeredmodelofstratification,mostsociologistsdescribetheclasssystemintheUnitedStatesasdividedintoseveralclasses:upper,uppermiddle,middle,lowermiddle,andlowerclass.Eachclassisdefinedbycharacteristicssuchasincome,occupationalprestige,andeducationalattainment.Thedifferentgroupsarearrayedalongacontinuumwiththosewiththemostmoney,education,andprestigeatthetopandthosewiththeleastatthebottom.IntheUnitedStates,theupperclassownsthemajorshareofcorporateandpersonalwealth;itincludesthosewhohaveheldwealthforgenerationsaswellasthosewhohaverecentlybecomerich.Onlyaverysmallproportionofpeopleactuallyconstitutetheupperclass,buttheycontrolvastamountsofwealthandpowerintheUnitedStates.Theyexerciseenormouscontrolthroughoutsociety.Mostoftheirwealthisinherited.→Despitesocialmythstothecontrary,thebestpredictoroffuturewealthisthefamilyintowhichyouareborn.Eachyear,thebusinessmagazineForbespublishesalistofthe"Forbes400"—thefourhundredwealthiestfamiliesandindividualsinthecountry.OfallthewealthrepresentedontheForbes400list,morethanhalfisinherited.Thoseonthelistwhocouldbecalled"self-made"werenottypicallyofmodestorigins;mostinheritedsignificantassets(Forbes,1997;SklarandCollins,1997).Thoseintheupperclasswithnewlyacquiredwealthareknownasthenouveauriche.Althoughtheymayhavevastamountsofmoney,theyareoftennotacceptedinto"oldrich"circles.→Theuppermiddleclassincludesthosewithhighincomesandhighsocialprestige.Theytendtobewell-educatedprofessionalsorbusinessexecutives.Theirearningscanbequitehighindeed--successfulbusinessexecutivescanearnmillionsofdollarsayear.Itisdifficulttoestimateexactlyhowmanypeoplefallintothisgroupbecauseofthedifficultyofdrawinglinesbetweentheupper,uppermiddle,andmiddleclass.Indeed,theuppermiddleclassisoftenthoughtofas"middleclass"becausetheirlifestylesetsthestandardtowhichmanyaspire,butthislifestyleissimplybeyondthemeansofamajorityofpeopleintheUnitedStates.→Themiddleclassishardtodefine;inpart,being"middleclass"ismorethanjusteconomicposition.ByfarthemajorityofAmericansidentifythemselvesasmiddleclasseventhoughtheyvarywidelyinlifestyleandinresourcesattheirdisposal.ButtheideathattheUnitedStatesisanopen-classsystemleadsmanytothinkthatthemajorityhaveamiddle-classlifestylebecause,ingeneral,peopletendnottowanttorecognizeclassdistinctionsintheUnitedStates.Thus,themiddleclassbecomestheubiquitousnormeventhoughmanywhocallthemselvesmiddleclasshaveatenuousholdonthisclassposition.Inthehierarchyofsocialclass,thelowermiddleclassincludesworkersintheskilledtradesandlow-incomebureaucraticworkers,manyofwhommayactuallydefinethemselvesasmiddleclass.Examplesareblue-collarworkers(thoseinskilledtradeswhodomanuallabor)andmanyserviceworkers,suchassecretaries,hairdressers,waitresses,police,andfirefighters.Mediumtolowincome,education,andoccupationalprestigedefinethelowermiddleclassrelativetotheclassgroupsaboveit.Theterm"lower"inthisclassdesignationreferstotherelativepositionofthegroupinthestratificationsystem,butithasapejorativesoundtomanypeople,especiallytopeoplewhoaremembersofthisclass.→Thelowerclassiscomposedprimarityofthedisplacedandpoor.Peopleinthisclasshavelittleformaleducationandareoftenunemployedorworkinginminimum-wagejobs.Fortypercentofthepoorwork;10percentworkyear-roundandfulltime—aproportionthathasgenerallyincreasedovertime.Recently,theconceptoftheunderclasshasbeenaddedtothelowerclass.TheunderclassincludesthosewhohavebeenleftbehindbyContemporaryeconomicdevelopments.Rejectedfromtheeconomicsystem,thoseintheunderclassmaybecomedependentonpublicassistanceorillegalactivities.

{{B}}ListeningComprehensionSectionDirections{{/B}}ThissectionmeasuresyourabilitytounderstandconversationsandlecturesinEnglish.Youwillheareachconversationorlectureonlyonetime.Aftereachconversationorlecture,youwillanswersomequestionsaboutit.Thequestionstypicallyaskaboutthemainideaandsupportingdetails.Somequestionsaskaboutaspeaker'spurposeorattitude.Answerthequestionsbasedonwhatisstatedorimpliedbythespeakers.Youmaytakenoteswhileyoulisten.Youmayuseyournotestohelpyouanswerthequestions.Yournoteswillnotbescored.Ifyouneedtochangethevolumewhileyoulisten,clickontheVolumeiconatthetopofthescreen.Insomequestions,youwillseethisicon:.Thismeansthatyouwillhear,butnotseepartofthequestion.Someofthequestionshavespecialdirections.Thesedirectionsappearinagrayboxonthescreen.Mostquestionsareworthonepoint.Ifaquestionisworthmorethanonepoint,itwillhavespecialdirectionsthatindicatehowmanypointsyoucanreceive.Youmustanswereachquestion.Afteryouanswer,clickonNext.ThenclickonOKtoconfirmyouranswerandgoontothenextquestion.AfteryouclickonOK,youcannotreturntopreviousquestions.Youwillhave20minutestoanswerthequestionsinthissection.Aclockatthetopofthescreenwillshowyouhowmuchtimeisremaining.Theclockwillnotcountdownwhileyouarelisteningtotestmaterial.{{B}}ChangingtheVolume{{/B}}Tochangethevolume,clickontheVolumeiconatthetopofthescreen.Thevolumecontrolwillappear.Movethevolumeindicatortotheleftortotherighttochangethevolume.Toclosethevolumecontrol,movethemousepointertoanotherpartofthescreen.Youwillbeabletochangethevolumeduringthetestifyouneedto.{{B}}Set1Conversation:ProblemwithAssignment{{/B}}{{B}}Narrator{{/B}}Listentoapartofalectureinamusicclass.

THE EFFECTS OF SLEEP DEPRIVATION1 Sleep restores the body and the mind and helps prevent disease by strengthening the immune system. However, many adults do not get the recommended eight hours of sleep each night. The average adult today gets only 6.4 hours of sleep, nearly an hour and a half less than what the average person received a century ago. {{U}}Only in recent years have health professionals begun to realize the prevalence and severity of sleep deprivation in the working population.{{/U}} A significant number of people work at night, work long shifts, or suffer from insomnia or jet lag. Others are {{U}}deprived of{{/U}} sleep because they work too hard, stay out too late, or try to do too many things in a day. Adults who regularly sleep six hours or less might think they accomplish more by staying up late, but they pay for it the next day when they feel sleepy or irritable or are unable to concentrate, remember things, or be very effective at their work. 2 Studies show that the brain is {{U}}adversely{{/U}} affected by sleep deprivation because certain patterns of electrical and chemical activity that occur during sleep are interrupted and the brain cannot function normally. In one study, thirteen healthy adult subjects who usually had normal sleep patterns were kept awake and carefully monitored in a hospital sleep laboratory during a period of 35 hours. During the experiment, the subjects were asked to perform several cognitive tasks, such as arithmetic and word problems, while undergoing magnetic resonance scans of their brain activity. The scans recorded each subject's brain activity from a rested state through various stages of sleep deprivation over the 35-hour period. The scans produced images showing increased activity in some regions of the brain and decreased activity in {{U}}others{{/U}}. The researchers found that the temporal lobe of the brain, the region involved in language processing, was activated during verbal tasks in rested subjects but not in sleep deprived subjects. When subjects were fully rested, their magnetic resonance scans showed that the temporal lobe was very active. However, after several hours without sleep, there was no activity within this region. The effects of the inactivity included slurred speech in the subjects who had gone for prolonged periods with no sleep. 3 Several studies show that getting fewer than six hours of sleep a night can impair short-term memory, coordination, reaction time, and judgment-thus posing a serious risk of accident or injury. In one study of drivers, researchers reported that sleep deprivation had some of the same hazardous effects as being drunk. They found that people who drove after being awake for 17 to 19 hours performed worse than those with a {{U}}blood alcohol level{{/U}} of .05 percent, the legal limit for drunk driving in most western European countries. The study also found that 16 to 60 percent of road accidents involved sleep deprivation. The researchers concluded that countries with drunk driving laws should consider similar restrictions against sleep-deprived driving. 4 There are other problems associated with sleep deprivation beyond impaired motor skills and judgment. Drivers who get too little sleep may have higher levels of stress, anxiety and depression, may take unnecessary risks, or may express rage toward other drivers. These dangers affect not only drivers but also people who work long shifts or night shifts, such as medical personnel and other emergency workers. The dangers of sleep deprivation go far beyond the obvious risks and can, in fact, undermine all areas of an individual's physical and mental health. 5 Sleep deprivation weakens the immune system, making an individual more prone to diseases such as the common cold and diabetes. Without sleep, the number of disease-fighting white blood cells within the body decreases, as does the activity of the remaining white blood cells. Sleep deprivation has been linked to a decrease in the body's production of hormones such as insulin. Results of a recent study suggested that healthy young adults who regularly got under 6.5 hours of sleep a night had greater insulin resistance than people who got 7.5 to 8.5 hours of sleep. Insulin resistance is a silent condition in which the pancreas does not make enough insulin or the body is unable to use the insulin that is present. Thus, the muscle and liver cells cannot metabolize the sugar called glucose. As a result, glucose builds up in the bloodstream, {{U}}setting the stage{{/U}} for diabetes and heart disease. Glcssary: insomnia: the inability to fall asleep or remain asleep jet lag: the disruption of bodily rhythms caused by high-speed travel across time zones cognitive: relating to mental processes

PRESTIGE 1 Prestige refers to a person's social standing--the level of respect that other people are willing to show. A person with high prestige is honored or esteemed by other people, while a person with low prestige is disrespected or marginalized. Prestige is a valued resource for people at all levels of a society, and this can be seen among inner-city youth, where to disrespect or "diss" someone has negative consequences. Exactly what qualities are respected will vary from one society to another. 2 In the United States, the top-status occupations are the professions--physicians, lawyers, professors, and clergy--requiring many years of education and training. At the other end of the hierarchy, the lowest prestige is associated with occupations requiring littie formal education--for example, bus drivers, sanitation workers, and janitors. Prestige is linked to income, but there are exceptions, such as college professors, who have high prestige but relatively low salaries compared to physicians and lawyers. Conversely, some low-prestige workers receive high union wages and benefits. Criminals are often well rewarded with income and respect in their communities, while politicians--many of whom are wealthy--are frequently less respected than occupations such as secretary and bank teller.

Whatisthetalkmainlyabout?A.HowAmericagottheTexasterritory.B.HowAmericagottheLouisianaterritory.C.HowAmericagottheOklahomaterritory.D.HowAmericagottheOhioterritory.

THE TRICKSTER FIGURE IN MYTHOLOGY 1 In the study of mythology, the character known as the trickster is a god, spirit, human, or animal who breaks the rules of the gods or nature, sometimes maliciously but usually with results that are positive. The rule breaking often takes the form of mischief or thievery . The trickster is usually male but occasionally disguises himself in female form. He can be cunning or foolish, or both, and often very humorous. His curiosity leads him into trouble, but he rescues himself with his sly wit. When he plays tricks, he performs important cultural tasks that benefit humans, and for this reason the trickster is a significant figure in world mythology. 2 In different cultures, the trickster and the hero are combined in various ways. In Greek mythology, Prometheus steals fire from the gods and gives it to humans, a feat making him more of a hero than a trickster, and he is usually portrayed as an intellectual. In many Native American stories, Coyote also steals fire from the gods, but Coyote is usually more of a jokester or a prankster than an intellectual. 3 The trickster is both creator and destroyer, giver and taker, one who tricks others and is tricked in return. The pranks of the trickster are compulsive and uncontrollable. He does not act consciously; he acts out of passion and impulse. He knows neither good nor evil, yet he is responsible for both. He possesses no morals, yet through his behavior morality comes into being. According to psychologist Carl Jung, the trickster is "a primitive cosmic being of divine-animal nature, on the one hand superior to man because of his superhuman qualities, and on the other hand inferior to him because of his unreason and unconsciousness." 4 In Native American mythology, the majority of trickster myths concern the creation or transformation of the earth. Such stories have a trickster who is always wandering, who is always hungry, who is not guided by normal ideas of good and evil, and who possesses some magical powers. In some stories he is a deity, and in others he is an animal or human that is subject to death. Several of these myths feature Raven or Coyote as the trickster-hero. 5 In many creation myths of the Pacific Northwest, Raven illustrates the transformational nature of tricksters. Raven is the greatest shapeshifter of all and can change into anything to get what he wants. In one story, there is darkness at the beginning of the world, so Raven decides he will find light. He flies far from the earth, searching in the darkness, until he spots a glimmer of light coming from a window in the house of the gods. Raven knows the gods are protective of their possessions, so he devises a trick. He perches on a pine branch next to the house and watches each day as the chief god"s daughter draws water from a nearby lake. He magically transforms himself into a pinyon seed and falls into the girl"s drinking cup. The girl swallows the seed, which grows within her body, and she eventually gives birth to a boy. The child delights his grandparents, and his laughter tricks the elder gods into revealing where they hide a shining ball of light. The gods give the child the ball to play with, and then Raven transforms back to a bird and flies off carrying the ball of light in his beak. He hangs the ball—the sun—in the sky, thereby bringing light to the world. 6 Coyote"s character is similar to that of Raven, and both appear in stories carrying out similar roles. In several stories from the American Southwest, Coyote steals fire from a group of "fire beings" and gives it to humans. In some tales Coyote wants to make human life more interesting, so he introduces sickness, sorrow, and death. He often teaches through negative example by employing the human vices of lying, cheating, and stealing. His tricks often bring about destructive natural phenomena, such as a great flood that destroys the earth. However, by causing the flood, Coyote leads the human race to a new and better world. Coyote shows us that at the heart of the trickster is a savior whose great gift to humans is showing them new ways of knowing and doing. Glossary: mischief: tendency to play tricks or cause minor trouble thievery: the act of theft; stealing pinyon seed: the seed of a pine tree; pine nut

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Whatisthetalkmainlyabout?A.Cultureshock.B.Ethnocentrism.C.Mythsandfolktales.D.Foodpreferences.