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 The story of gold is an adventure involving kings, queens, pirates, explorers, conquerors, and the native peoples they conquered. Throughout history, gold has woven a magic spell over those it touched. Gold is beautiful and rare; a soft shiny metal that can be moulded into many (1)...... . It has been used for money, jewelry, and to decorate special buildings such as palaces and places of worship. (2)......the precious metal was discovered, prospectors rushed to mine it, starting new cities and countries as they went. Gold and the people who love it have helped shape the world we live (3).........today. Gold is one of many elements, or substances that cannot be changed by normal chemical means, that are found in the Earth's crust. Gold has a warm, sunny colour and (4)......... it does not react with air, water, and most chemicals, its shine never fades. In its natural (5)........... , gold is soft and easily shaped. When heated to 1,062 Celsius it melts and can be poured into moulds to form coins, gold bars, and other objects. Stories have been told, movies made and legends bom about the discovery of the world’s great gold deposits. It is a saga of dreams, greed, ambition and exploration.
(1)...................................

 

It's called 42 - the name taken from the answer to the meaning of life, from the science fiction series The Hitchhiker's Guide to the Galaxy. 42 was founded by French technology billionaire Xavier Niel, whose backing means there are no tuition fees and accommodation is free. Mr Niel and his co-founders come from the world of technology and start-ups, and they are trying to do to education what Facebook did to communication and Airbnb to accommodation.
Students at 42 are given a choice of projects that they might be set in a job as a software engineer - perhaps to design a website or a computer game. They complete a project using resources freely available on the Internet and by seeking help from their fellow students, who work alongside them in a large open-plan room full of computers. Another student will then be randomly assigned to mark their work.
The founders claim this method of learning makes up for shortcomings in the traditional education system, which they say encourages students to be passive recipients of knowledge. "Peer-to-peer learning develops students with the confidence to search for solutions by themselves, often in quite creative and ingenious ways."
Like in computer games, the students are asked to design and they go up a level by completing a project. They graduate when they reach level 21, which usually takes three to five years. And at the end, there is a certificate but no formal degree. Recent graduates are now working at companies including IBM, Amazon, and Tesla, as well as starting their own firms.
"The feedback we have had from employers is that our graduates are more apt to go off and find out information for themselves, rather than asking their supervisors what to do next," says Brittany Bir, chief operating officer of 42 in California and a graduate of its sister school in Paris. Ms Bir says 42's graduates will be better able to work with others and discuss and defend their ideas - an important skill in the “real world” of work. "This is particularly important in computer programming, where individuals are notorious for lacking certain human skills," she says. 
But could 42's model of teacher less learning work in mainstream universities? Brittany Bir admits 42's methods do not suit all students. "It suits individuals who are very disciplined and self-motivated, and who are not scared by having the freedom to work at their own pace," she says.

The word “them” in paragraph 2 refers to ..........

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Vitamins, taken in tiny doses, are a major group of organic compounds that regulate the mechanisms by which the body converts food into energy. They should not be confused with minerals, which are inorganic in their makeup. Although in general the naming of vitamins followed the alphabetical order of their identification, the nomenclature of individual substances may appear to be somewhat random and disorganized. Among the 13 vitamins known today, five are produced in the body. Because the body produces sufficient quantities of some but not all vitamins, they must be supplemented in the daily diet. Although each vitamin has its specific designation and cannot be replaced by another compound, a lack of one vitamin can interfere with the processing of another. When a lack of even one vitamin in a diet is continual, a vitamin deficiency may result.
The best way for an individual to ensure a necessary supply of vitamins is to maintain a balanced diet that includes a variety of foods and provides adequate quantities of all the compounds. Some people take vitamin supplements, predominantly in the form of tablets. The vitamins in such supplements are equivalent to those in food, but an adult who maintains a balanced diet does not need a daily supplement. The ingestion of supplements is recommended only to correct an existing deficiency due to unbalanced diet, to provide vitamins known to be lacking in a restricted diet, or to act as a therapeutic measure in medical treatment. Specifically, caution must be exercised with fat-soluble substances, such as vitamins A and D, because, taken in gigantic doses, they may present a serious health hazard over a period of time.

How many vitamins must be derived from nourishment?

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George Washington Carver showed that plant life was more than just food for animals and humans. Carver’s first step was to analyze plant parts to find out what they were made of. He then combined these simpler isolated substances with other substances to create new products.
The branch of chemistry that studies and finds ways to use raw materials from farm products to make industrial products is called chemurgy. Carver was one of the first and greatest chemurgists of all time. Today the science of chemurgy is better known as the science of synthetics. Each day people depend on and use synthetic materials made from raw materials. All his life Carver battled against the disposal of waste materials and warned of the growing need to develop substitutes for the natural substances being used up by humans.
Carver never cared about getting credit for the new products he created. He never tried to patent his discoveries or get wealthy from them. He turned down many offers to leave Tuskegee Institute to become a rich scientist in private industry. Thomas Edison, inventor of the electric light, offered him a laboratory in Detroit to carry out food research. When the United States government made him a collaborator in the Mycology and Plant Disease Survey of the Department of Agriculture, he accepted the position with the understanding that he wouldn’t have to leave Tuskegee. As an authority on plant diseases – especially of the fungus variety – Carver sent hundreds of specimens to the United States Department of Agriculture. At the peak of his career, Carver’s fame and influence were known on every continent.

The word “step” in paragraph 1 could best be replaced with

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Martin Luther King, Jr., is well known for his work in civil rights and for his many famous speeches, among them is his moving “I Have A Dream” speech. But fewer people know much about King’s childhood. M.L., as he was called, was born in 1929 in Atlanta, Georgia, at the home of his maternal grandfather. M.L.’s grandfather, the Reverend A.D. Williams, purchased their home on Auburn Avenue in 1909, twenty years before M.L. was born. The Reverend Williams, an eloquent speaker, played an important role in the community since so many people’s lives centered around the church. He allowed his church and his home to be used as a meeting place for a number of organizations dedicated to the education and social advancement of blacks.
M.L. grew up in this atmosphere, with his home being used as a community gathering place, and was no doubt influenced by it.

M.L.’s childhood was not especially eventful. His father was a minister and his mother was a musician. He was the second of three children, and he attended all-black schools in a black neighborhood. The neighborhood was not poor, however. Auburn Avenue was the main artery through a prosperous neighborhood that had come to symbolize achievement for Atlanta’s black people. It was an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other black-owner, black- operated businesses, and services. Even in the face of Atlanta’s segregation, the district thrived. Dr. King never forgot the community spirit he had known as a child, nor did he forget the racial prejudice that was a seemingly insurmountable barrier that kept black Atlanta from mingling with whites.

What is this passage mainly about?

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Fifty-five delegates representing all thirteen states except Rhode Island attended the Constitutional Convention in Philadelphia from May to September 1787. The delegates had been instructed by the Continental Congress to revise the old Articles of Confederation, but most believed that a stronger central government was needed. There were differences, however, about what structure the government should take and how much influence large states should have.
Virginia was by far the most populous state, with twice as many as people as New York, four times as many as New Jersey, and ten times as many as Delaware. The leader of the Virginia delegation, James Madison, had already drawn up a plan for government, which became known as the Large State Plan. Its essence was that congressional representation would be based on population. It provided for two or more national executives. The smaller states feared that under this plan, a few large states would lord over the rest. New Jersey countered with the Small State Plan. It provided for equal representation for all states in a national legislature and for a single national executive. Angry debate, heightened by a stifling heat wave, led to deadlock.
A cooling of tempers seemed to come with lower temperatures. The delegates hammered out an agreement known as the Great Compromise- actually a bundle of shrewd compromises. They decided that Congress would consist of two houses. The larger states were granted representation based on population in the lower house, the House of Representatives. The smaller states were given equal representation in the upper house, the Senate, in which each state would have two senators regardless of population. It was also agreed that there would be a single executive, the president. This critical compromise broke the logjam, and from then on, success seemed within reach.

The word “shrewd” is closest in meaning to

Of all the aspirations which make up the American Dream, perhaps the most prominent is to own one’s own home. Americans are very proud of their homes and spend a great deal of time maintaining their houses and keeping the property in good condition. A man's home is often called his castle, and the hours spent keeping his fortress safe and secure become one of his greatest pleasures.
If a home is in an especially fashionable neighborhood, the owners may consult an interior decorator to give the home a certain coordinated appearance. If there is a large back yard, great care may be spent in having it properly landscaped with exotic trees, shrubs and plants.
It is almost a certainty that you should be the first visitor to an American home, you will be taken on a grand tour of the premises. The owner will take great pride in showing to you the place he calls home. Every closet, every cabinet and closed door will be opened so that you can actually see the extent and value of his home. You will even be taken into the father's den and the mother's sewing room. These are special rooms for the respective man and woman of the house to insure their privacy. They may be off-limits to the rest of the family but, for the visitor they are open to scrutiny and inspection.
It is, of course, considered polite on the tour to comment favorably on each room picking out its most salient, important feature, such as the special view from the window, the vaulted ceiling in the foyer or the exotic choice of wallpaper in the bathroom.
The finished basement is a special cause for pride for the family with its exercise room, video games, carpenter shop and launderette. In most homes it is here that the family entertains itself in the evening while the rest of the house becomes more of a showcase. On your tour you may be reminded of the hours the owners had spent "fixing up the house" so it would be "nice for the kids to bring over their friends". You may even sense a feeling of competition in knowing that they have not only "kept up with the Joneses" but also have far surpassed them.
The tour will terminate after an hour or so somewhere on the back lawn next to the two-car air- conditioned garage where you may be treated to a snack and light refreshment.
Showing off one's home is more than an exercise in vanity. It is a tribute to one's accomplishment. It is a way of saying that a man has been a good provider for his family and that he has realized one of his dreams.

What is meant by "keep up with the Joneses"?

Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage:

"Before the 1960s, Singapore was essential a trading nation. Since (1)….. , it has developed a more (2)…. economy and has become an important financial, trade, and transportation center. Singapore has (3)….. banks, insurance, and finance companies, as (4) …..  as a stock exchange. Tourism is also important to the (5)…. of Singapore.
 There is (6)…. unemployment in Singapore. The country’s annual income per capita (per person) is one of the (7) …. in Asia. The government of Singapore plays a major role in the country’s economy. For example, it (8)….. what benefits, such as vacation time and sick leave, must be (9)….for workers by employers. It also operates an employment agency to help people find jobs, and it provides (10)…..  for retired workers."

4 , as (4) …..  as a stock exchange.

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Every year about two million people visit Mount Rushmore, were the faces of four U.S presidents were carved in granite by sculptor Gutzon Borglum and his son, the late Lincoln Borglum. The creation of the Mount Rushmore monument Line took 14 years – from 1927 to 1941 – and nearly a million dollars. There were times when money was difficult to come by and many people were jobless. To move more than 400,000 tons of rock, Borglum hired laid-off workers from the closed-down mines in the Black Hills area. He taught these men to dynamite, drill, carve, and finish the granite as they were hanging in midair in his specially devised chairs, which had many safety features. Borglum was proud of the fact that no workers were killed or severely injured during the years of blasting and carving.
During the carving, many changes in original design had to be made to keep the carved heads free of large fissures that were uncovered. However, not all the cracks could be avoided, so Borglum concocted a mixture of granite dust, white lead, and linseed oil to fill them.
Every winter, water from melting snows gets into the fissures and expands as it freezes, making the fissures bigger. Consequently, every autumn maintenance work is done to refill the cracks. The repairers swing out in space over a 500-foot drop and fix the monument with the same mixture that Borglum used to preserve this national monument for future generations.

According to the passage, Borglum’s son _     

Read the passage and choose the best answers:

In the United States and Canada, it is very important to (1)___________ a person directly in the eyes when you are having a conversation with him or her. If you look down or to the side when the other person is talking, that person will think that you are not interested in (2)___________ he or she is saying. This, (3) __________is not polite. If you look down or to the side when you are talking, it might seem that you are not honest.

However, people who are speaking will sometimes look away for a few seconds when they are thinking or (4)______________ to find the right word. But they always turn immediately back to look the listener directly in the eyes. These social "rules" are (5)___________ for two men, two women, a man and a woman, or an adult and a child.

(2)___________

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Washington was the first city in history to be created solely for the purpose of governance. Following the Revolution, members of Congress had hotly debated the question of a permanent home for themselves and for those departments – the Treasury, the Patent Office and so on – which even the sketchiest of central governments would feel obliged to establish. In 1790, largely in order to put an end to congressional bickering, George Washington was charged with selecting a site for the newly designated federal district. Not much to anyone’s surprise but to the disappointment of many he chose a tract of land on the banks of the Potomac River, a few miles upstream from his beloved plantation Mount Vernon.
The District of Columbia was taken in part from Virginia and in part from Maryland. At the time it was laid out, its hundred square miles consisted of gently rolling hills, some under cultivation and the rest heavily wooded, with a number of creeks and much swampy land along the Potomac. There is now a section of Washington that is commonly referred to as Foggy Bottom; that section bore the same nickname a hundred and eighty years ago.
Two ports cities, Alexandria and Georgetown, flourished within sight of the new capital and gave it access by ship to the most important cities of the infant nation – Charleston, Baltimore, Philadelphia, New York, Newport, Salem and Portsmouth – and also to the far-off ports of England and the Continent.

The author implies that Georgetown was important in the eighteen century because it

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Being aware of one's own emotions - recognizing and acknowledging feelings as they happen - is at the very heart of Emotional Intelligence. And this awareness encompasses not only moods but also thoughts about those moods. People who are able to monitor their feelings as they arise are less likely to be ruled by them and are thus better able to manage their emotions.
Managing emotions does not mean suppressing them; nor does it mean giving free rein to every feeling. Psychologist Daniel Goleman, one of several authors who have popularized the notion of Emotional Intelligence, insisted that the goal is balance and that every feeling has value and significance. As Goleman said, "A life without passion would be a dull wasteland of neutrality, cut off and isolated from the richness of life itself." Thus, we manage our emotions by expressing them in an appropriate manner. Emotions can also be managed by engaging in activities that cheer us up, soothe our hurts, or reassure us when we feel anxious.
Clearly, awareness and management of emotions are not independent. For instance, you might think that individuals who seem to experience their feelings more intensely than others would be less able to manage them. However, a critical component of awareness of emotions is the ability to assign meaning to them - to know why we are experiencing a particular feeling or mood. Psychologists have found that, among individuals who experience intense emotions, individual differences in the ability to assign meaning to those feelings predict differences in the ability to manage them. In other words, if two individuals are intensely angry, the one who is better able to understand why he or she is angry will also be better able to manage the anger.
Self-motivation refers to strong emotional self-control, which enables a person to get moving and pursue worthy goals, persist at tasks even when frustrated, and resist the temptation to act on impulse. Resisting impulsive behavior is, according to Goleman, "the root of all emotional self-control."
Of all the attributes of Emotional Intelligence, the ability to postpone immediate gratification and to persist in working toward some greater future gain is most closely related to success - whether one is trying to build a business, get a college degree, or even stay on a diet. One researcher examined whether this trait can predict a child's success in school. The study showed that 4-year-old children who can delay instant gratification in order to advance toward some future goal will be "far superior as students" when they graduate from high school than will 4-year-olds who are not able to resist the impulse to satisfy their immediate wishes.

Which of the following can we infer from paragraph 1?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.
              THE FUTURE OF WATER
Many of us often wonder what the future holds; some believe major advances in technology will occur which will result in improvements to our everyday lives. Scientists have predicted shortages in fossil fuels and changes in the weather patterns of the world. (1).......... , one significant change that will have an alarming impact on all of us is the global water shortage. Analysts have forecast that some of the consequences of this will be mass migration from Africa to Europe and wars between countries over clean water. The main causes of this disturbing water shortage are global warming, climate change and the increasing world population. The supply of fresh water (2)....... comes from mountain glaciers and  flows  into  lakes  and  rivers  is  diminishing,  and  this also (3).......... to the shortage. Water analysts and government leaders need to start making radical changes to the way water use is managed and they need to find new sources that will be able to meet the demands of an ever-growing population.  In addition, more things need to be done to control global warming as this will help to reduce water shortages.   People   should   be made  (4)......... of the situation and warned not to waste water. Multinational companies should invest in developing better water management systems. In summary, if we start (5) ............. action now, we might be able to prevent a world disaster.
(4).................................

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Theresa May, the second female Britain’s prime minister following Margaret Thatcher, revealed in 2013 that she had been given a diagnosis of Type 1 diabetes, a condition that requires daily insulin injections. Asked later how she felt about the diagnosis, she said her approach to it was the same as toward everything in her life: “Just get on and deal with it.” That kind of steeliness brought her to center stage in the aftermath of Britain’s vote to leave the European Union and the feuding that erupted in the Conservative Party over who would succeed David Cameron.
Ms” May, 59 years old, is the country’s longest-serving home secretary in half a century, with a reputation for seriousness, hard work and above all, determination. She is one of a growing number of women in traditionally male-dominated British politics rising to the upper position of leadership.
Bom in 1956, Ms. May grew up mainly in Oxford shire, an only child who was first drawn to the Conservative Party at age 12. As a conscientious student, she never rebelled against her religious upbringing and remains a regular churchgoer. Tellingly, her sports hero was Geoffrey Boycott, a solid, stubborn cricketer who specialized in playing the long game.
Like many other Britain’s prime minister including Tony Blair, Sir Robert Peel and Margaret Thatcher, she won a place at Oxford. But while almost every other political leader got there by way of Eton College and joined Oxford’s hedonistic Bullingdon Club, she attended a state secondary school and had a more sedate university career. After unsuccessful attempts to be elected to the House of Commons in 1992 and 1994, she finally became an MP in 1997 general election.
May is known for a love of fashion and in particular distinctive shoes. She even wore leopard-print shoes to her final Cabinet meeting as Home Secretary in early 2016. However, she has been quite critical of the media focusing on her fashion instead of her achievement as a politician. May also describes cooking and walking as primary hobbies, and if someone is raising questions about why walking can be classified as a hobby, she elaborates in a column for Balance magazine, in which she wrote of her battle with diabetes.

Which of the following statements is NOT true?

Choose the item among A, B, C or D that best answers the question about the passage:

"When Franklin Roosevelt was elected President of the United States in 1932. not only the United States but also the rest of the world was in the throes of an economic depression. Following the termination of World War I, Britain and the United States at first experienced a boom in industry. Called the Roaring Twenties, the 1920s ushered in a number of things - prosperity, greater equality for women in the work world, rising consumption, and easy credit. The Outlook for American business was rosy.
 October 1929 was a month that had catastrophic economic reverberation worldwide. The American stock market witnessed the “Great Crash,” as it is called, and the temporary boom in the American economy came to a standstill. Stock prices sank, and panic spread. The ensuing unemployment figure soared to 12 million by 1932.
 Roosevelt was elected because he promised a “New Deal” to lift the United States out of the doldrums of the depression. Following the principles advocated to Keynes, a British economist, Roosevelt mustered the spending capacities of the federal government to provide welfare, work, and agricultural aid to the millions of down-and-out Americans. Roosevelt succeeded in dragging the nation out of the Depression before the outbreak of World War II."

1. A good title for this passage would be ………..

Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage:

"Before the 1960s, Singapore was essential a trading nation. Since (1)….. , it has developed a more (2)…. economy and has become an important financial, trade, and transportation center. Singapore has (3)….. banks, insurance, and finance companies, as (4) …..  as a stock exchange. Tourism is also important to the (5)…. of Singapore.
 There is (6)…. unemployment in Singapore. The country’s annual income per capita (per person) is one of the (7) …. in Asia. The government of Singapore plays a major role in the country’s economy. For example, it (8)….. what benefits, such as vacation time and sick leave, must be (9)….for workers by employers. It also operates an employment agency to help people find jobs, and it provides (10)…..  for retired workers."

2. it has developed a more (2)…. economy and has become an important financial, trade, and transportation center. 

Choose the word or phrase that best fits each space in the following passage

THE FIRST WOMAN SCIENTIST

Hypatia was born in Alexandria, in Egypt, in 370 A.D. For many centuries, she was the only woman (1) ___________ to have a place in the history books. Hypatia's father was the director of Alexandria University, and he (2) ______________ sure his daughter had the best education available. This was unusual, as most women then had few opportunities to study.

After studying in Athens and Rome, Hypatia returned to Alexandria (3)_______ she began teaching  mathematics. She soon became famous for her knowledge of new ideas.

There are no copies of her books, but it is said that she wrote several important mathematical works. Hypatia was also interested in technology and (4)___________ several scientific tools to help with her work.

At the time, many rulers were afraid of science, and something connected with it was (5)_________ danger. One day in March 415, Hypatia was attacked in the street and killed.

During the 20th century, Hypatia was seen as a symbol of the women's rights movement, a precursor to the feminist movement. Since the late 20th century, Hypatia's death has at times been associated with the destruction of the Library of Alexandria, although historically the library ceased to exist in Hypati.

(3) _________

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These days in business, people have to face many challenging questions when designing and implementing new projects in undeveloped areas of the countryside. One issue which has to be faced is whether it is possible to introduce new technology without destroying the local environment. Economic (1)..... and environmental conservation are often seen as natural enemies. It is unfortunate that in the past this has often been true, and it has been necessary to choose between (2)......the project or protecting the environment. However, by taking environmental considerations (3)........ at an early stage in a project, companies can significantly reduce any impact on local plants and animals. For example, in southern Africa, a company called CEL was asked to put up 410 km of a power transmission line without disturbing the rare birds which inhabit that area. The project was carried out with (4)....... disturbance last summer. What may surprise many business people is the fact that this consideration for local wildlife did not in any way slow down the project. Indeed, the necessary advance  planning combined  with  local  knowledge  and  advanced technology, (5).......... that  the  project  was actually completed ahead of schedule. CEL was contracted to finish the job by October and managed to do so two months earlier.
(1).........................

Millions of people are using cellphones today. In many places, it is actually considered unusual not to use one. In many countries, cellphones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected.
The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.
On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree.
What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about.
As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too often.

According to the passage, cellphones are especially popular with young people because  .............

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In this modern world where closed-circuit television (CCTV) cameras are everywhere and smartphones in every pocket, the routine filming of everyday life is becoming pervasive. A number of countries are rolling out body cams for police officers; other public-facing agencies such as schools, councils and hospitals are also experimenting with cameras for their employees. Private citizens are getting in on the act too: cyclists increasingly wear headcams as a deterrent to aggressive drivers. As camera technology gets smaller and cheaper, it isn't hard to envisage a future where we're all filming everything all the time, in every direction.
Would that be a good thing? There are some obvious potential upsides. If people know they are on camera, especially when at work or using public services, they are surely less likely to misbehave. The available evidence suggests that it discourages behaviours such as vandalism. Another upside is that it would be harder to get away with crimes or to evade blame for accidents.
But a world on camera could have subtle negative effects. The deluge of data we pour into the hands of Google, Facebook and others has already proved a mixed blessing. Those companies would no doubt be willing to upload and curate our body-cam data for free, but at what cost to privacy and freedom of choice?
Body-cam data could also create a legal minefield. Disputes over the veracity and interpretation of police footage have already surfaced. Eventually, events not caught on camera could be treated as if they didn't happen. Alternatively, footage could be faked or doctored to dodge blame or incriminate others.
Of course, there's always the argument that if you're not doing anything wrong, you have nothing to fear. But most people have done something embarrassing, or even illegal, that they regret and would prefer they hadn't been caught on film. People already censor their social media feeds – or avoid doing anything incriminating in public – for fear of damaging their reputation. Would ubiquitous body cams have a further chilling effect on our freedom?
The always-on-camera world could even threaten some of the attributes that make us human. We are natural gossips and backbiters, and while those might not be desirable behaviours, they oil the wheels of our social interactions. Once people assume they are being filmed, they are likely to clam up.
The argument in relation to body-cam ownership is a bit like that for guns: once you go past a critical threshold, almost everyone will feel they need one as an insurance policy. We are nowhere near that point yet – but we should think hard about whether we really want to say "lights, body cam, action." 

The phrase "a mixed blessing" in paragraph 3 probably means     .

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What geologists call the Basin and Range Province in the United States roughly coincides in its northern portions with the geographic province known as the Great Basin. The Great Basin is hemmed in west by the Sierra Nevada and on the east Line by the Rocky Mountains; it has no outlet to the sea. The prevailing winds in the Great Basin are from the west. Warm, moist air from the Pacific Ocean is forced upward as it crosses the Sierra Nevada. At the higher altitudes it cools and the moisture it carries is precipitated as rain or snow on the western slopes of the mountains. That which reaches the Basin is air wrung dry of moisture. What little water falls there as rain or snow, mostly in the winter months, evaporates on the broad, flat desert floors. It is, therefore, an environment in which organisms battle for survival. Along the rare watercourses, cottonwoods and willows eke out a sparse existence. In the upland ranges, pinion pines and junipers struggle to hold their own.
But the Great Basin has not always been so arid. Many of its dry, closed depressions were once filled with water. Owens Valley, Panamint Valley, and Death Valley were once a string of interconnected lakes .The two largest of the ancient lakes of the Great Basin were Lake Lahontan and Lake Bonneville. The Great Salt Lake is all that remains of the latter, and Pyramid Lake is one of the last briny remnants of the former. There seem to have been several periods within the last tens of thousands of years when water accumulated in these basins. The rise and fall of the lakes were undoubtedly linked to the advances and retreats of the great ice sheets that covered much of the northern part of the North American continent during those times.
Climatic changes during the Ice Ages sometimes brought cooler, wetter weather to mid latitude deserts worldwide, including those of the Great Basin. The broken valleys of the Great Basin provided ready receptacles for this moisture.

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