Bees, classified into over 10,000 species, are insects found in almost every part of the world except the northernmost and southernmost regions. One commonly known species is the honeybee, the only bee that produces honey and wax. Humans use the wax in making candles, lipsticks, and other products, and they use the honey as a substance that people eat to maintain life and growth. While gathering the nectar and pollen with which they make honey, bees are simultaneously helping to fertilize the flowers on which they land. Many fruits and vegetables would not survive if bees did not carry the pollen from blossom to blossom.
Bees live in a structured environment and social structure within a hive, which is a nest with storage space for the honey. The different types of bees each perform a unique function. The worker bee carries nectar to hive in a special stomach called a honey stomach. Other workers make beeswax and shape it into a honeycomb, which is a waterproof mass of six-sided compartments, or cells. The queen lays eggs in completed cells. As the workers build more cells, the queen lays more eggs.
All workers, like the queen, are female, but the workers are smaller than the queen. The male honeybees are called drones; they do no work and cannot sting. They are developed from unfertilized eggs, and their only job is to impregnate a queen. The queen must be fertilized in order to lay more worker eggs. During the season when less honey is available and the drone is of no further use, the workers block the drones from eating the honey so that they will starve to death.

According to the passage, the drone  ..........

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Edward Patrick Francis “Eddie” Eagan (April 26, 1897-June 14, 1967), was an amateur boxing star of the early 1920s. He was born into a poor family in Denver, Colorado. His father died in a railroad accident when Eagan was only a year old. He and his four brothers were raised by his mother, who earned a small income from teaching foreign languages.
Inspired by Frank Merriwell, the hero of a series of popular novels for boys, Eagan pursued an education for himself as well as an interest in boxing. He attended the University of Denver for a year before serving in the U.S. Army as an artillery lieutenant during World War I. After the war, he entered Yale University and, while studying there, won the U.S. national amateur heavyweight boxing title. He graduated from Yale in 1921, attended Harvard Law School, and received a Rhodes scholarship to the University of Oxford where he received his Master’s Degree in 1928.
While studying at Oxford, Eagan became the first American to win the British amateur boxing championship. Eagan won his first Olympic gold medal as a light heavyweight boxer at the 1920 Olympic Games in Antwerp, Belgium. Eagan also fought at the 1924 Olympics in Paris as a heavyweight but failed to get a medal.
Though he had taken up the sport just three weeks before the competition, he managed to win a second gold medal as a member of the four-man bobsled team at the 1932 Olympics in Lake Placid, New York. Thus he became the only athlete to win gold medals at both the Summer and Winter Olympics.
Eagan was a member of the first group of athletes inducted into the U.S. Olympic Hall of Fame in 1983. Eagan became a respected attorney, serving as an assistant district attorney for southern New York and as chairman of the New York State Athletic Commission (1945-51). He married soap heiress. Margaret Colgate and attained the rank of lieutenant colonel during World War II. He died at the age of 70, in Rye, New York.

According to the passage, where were the 1920 Olympic Games held?

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Geothermal energy is natural heat from the interior of the Earth that is converted to heat buildings and generate electricity. The idea of harnessing Earth’s internal heat is not new. As early as 1904 , geothermal power was used in Italy . Today, Earth’s natural internal heat is being used to generate electricity in 21 countries , including Russia, Japan, New Zealand, Iceland, Mexico, Ethiopia, Guatemala, EI Salvador, the Philippines, and the United States .Total worldwide production is approaching 9,000 MW (equivalent to nine large modern coal-burning or nuclear power plants)-double the amount in 1980 .Some 40 million people today receive their electricity from geothermal energy at a cost competitive with that of other energy sources. In EI Salvador , geothermal energy is supplying 30% of the total electric energy used.
However, at the global level, geothermal energy supplies less than 0,15%of the total energy supply.
Geothermal energy may be considered a nonrenewable energy source when rates of extraction are greater than rates of natural replenishment. However, geothermal energy has its origin in the natural heat production within Earth , and only a small fraction of the vast total resource base is being utilized today. Although most geothermal energy production involves the tapping of high heat sources, people are also using the low-temperature geothermal energy of groundwater in some applications.

Geothermal Systems
The average heat flow from the interior of the Earth is very low, about 0,06% W/m2.This amount is trivial compared with the 177 W/m2from solar heat at the surface in the United States. However, in some areas, heat flow is sufficiently high to be useful for producing energy . For the most part, areas of high heat flow are associated with plate tectonic boundaries. Oceanic ridge systems (divergent plate boundaries) and areas where mountains are being uplifted and volcanic island arcs are forming (convergent plate boundaries) are areas where this natural heat flow is anomalously high. One such region is located in the western, United States, where recent tectonic and volcanic activity has occurred.
On the basis of geological criteria, several types of hot geothermal systems (with temperatures greater than about 800C , or 1760F)have been defined, and the resource base is larger than that of fossil fuels and nuclear energy combined. A common system for energy development is hydrothermal convection, characterized by the circulation of steam and / or hot water that transfers heat from depths to the surface.

Read the following passage and choose among A, B, C or D the correct answer to each of the questions.

FIRST TIME IN THE AIR

When John Mills was going to fly in an aero plane for the first time, he was frightened.

He did not like the idea of being thousands of feet up in the air. "I also didn't like the fact that I wouldn't be in control," says John.

"I'm a terrible passenger in the car. When somebody else is driving, I tell them what to so. It drives everybody crazy."

However John couldn't avoid flying any longer. It was the only way he could visit his grandchildren in Canada.

"I had made up my mind that I was going to do it, I couldn't let my son, his wife and their three children travel all the way here to visit me. It would be so expensive for them and I know Tom's business isn't doing so well at the moment - it would also be tiring for the children - it's a nine-hour flight!" he says.

To get ready for the flight John did lots of reading about aero planes. When he booked his seat, he was told that he would be flying on a Boeing 747, which is better known as a jumbo jet. "I needed to know as much as possible before getting in that plane. I suppose it was a way of making myself feel better. The Boeing 747 is the largest passenger aircraft in the world at the moment. The first one flew on February 9th 1969 in the USA. It can carry up to 524 passengers and 3.400 pieces of luggage. The fuel for aero planes is kept in the wings and the 747 is wings are so big that they can carry enough fuel for an average car to be able to travel 16,000 kilometers a year for 70 years. Isn't that unbelievable? Even though I had discovered all this very interesting information about the jumbo, when I saw it for the first time, just before I was going to travel to Canada, I still couldn't believe that something so enormous was going to get up in the air and fly. I was even more impressed when I saw how big it was inside with hundreds of people!"

The biggest surprise of all for John was the flight itself. "The take-off itself was much smoother than I expected although I was still quite scared until we were in the air. In the end, I managed to relax, enjoy the food and watch one of the movies and the view from the window was spectacular. I even managed to sleep for a while! Of course," continues John, "the best reward of all was when I arrived in Canada and saw my son and his family, particularly my beautiful grandchildren. Suddenly, I felt so silly about all the years when I couldn't even think of getting on a plane. I had let my fear of living stop me from seeing the people I love most in the world. I can visit my son and family as often as I like now!"

What happened when he saw the jumbo jet for the first time?

Since the dawn of time, people have found ways to communicate with one another. Smoke signals and tribal drums were some of the earliest forms of communication. Letters, carried by birds or by humans on foot or on horseback, made it possible for people to communicate larger amounts of information between two places. The telegram and telephone set the stage for more modern means of communication. With the invention of the cellular phone, communication itself has become mobile.
For you, a cell phone is probably just a device that you and your friends use to keep in touch with family and friends, take pictures, play games, or send text message. The definition of a cell phone is more specific: it is a hand- held wireless communication device that sends and receives signals by way of small special areas called cells.
Walkie - talkies, telephones and cell phones are duplex communication devices: They make it possible for two people to talk to each other. Cell phones and walkie- talkies are different from regular phones because they can be used in many different locations. A walkie- talkie is sometimes called a half- duplex communication device because only one person can talk at a time. A cell phone is a full- duplex device because it uses both frequencies at the same time. A walkie-talkie has only one channel. A cell phone has more than a thousand channels. A walkie- talkie can transmit and receive signals across a distance of about a mile. A cell phone can transmit and receive signals over hundreds of miles. In 1973, an electronic company called Motorola hired Martin Cooper to work on wireless communication. Motorola and Bell Laboratories (now AT& T) were in a race to invent the first portable communication device.
Martin Cooper won the race and became the inventor of the cell phone. On April 3, 1973, Cooper made the first cell phone call to his opponent at AT& T while walking down the streets of New York city. People on the sidewalks gazed at cooper in amazement. Cooper's phone was called A Motorola Dyna- Tac. It weighed a whopping 2.5 pounds (as compared to today's cell phones that weigh as little as 3 or 4 ounces)
After the invention of his cell phone, Cooper began thinking of ways to make the cell phone available to the general public. After a decade, Motorola introduced the first cell phone for commercial use. The early cell phone and its service were both expensive. The cell phone itself cost about $ 3, 500. In 1977, AT & T constructed a cell phone system and tried it out in Chicago with over 2, 000 customers. In 1981, a second cellular phone system was started in the Washington,D.C and Baltimore area. It took nearly 37 years for cell phones to become available for general public use. Today, there are more than sixty million cell phone customers with cell phones producing over thirty billion dollars per years.

The word "duplex" is closest meaning to ............

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Genetic modification of foods is not a new practice. It has been practiced for thousands of years under the name of "selective breeding". Animals and plants were chosen because they had traits that humans found useful. Some animals were larger and stronger than others, or they yielded more food, or they had some other trait that humans valued. Therefore, they were bred because of those traits. Individuals with those traits were brought together and allowed to breed in the hope that their offspring would have the same traits in greater measure.
Much the same thing was done with plants. To produce bigger or sweeter fruit, or grow more grain per unit of land, strains of plants were combined and recombined to produce hybrids, or crossbreeds that had the desired traits in the right combinations. All the while, however, biologists wondered: is there a more direct and versatile way to change the traits of plants and animals? Could we rewrite, so to speak, the heredity of organisms to make them serve our needs better?
In the 20th century, genetic modification made such changes possible at last. Now, it was possible to alter the genetic code without using the slow and uncertain process of selective breeding. It even became possible to blend plants and animals genetically: to insert animal genes into plants, for example, in order to give the plants a certain trait they ordinarily would lack, such as resistance to freezing. The result was a tremendous potential to change the very nature of biology.

What is the passage mainly about?

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The problem of cardiac arrest has become a major problem these days. A lot of patients have acute pain after suffering from a stroke. There are plenty of medicines, surgical methods developed in the field of medicine to treat such cardiac problems. These solutions are time consuming and costly. In the process of rehabilitation, the medicines also have a lot of side effects on the human body and take time to give relief. Therefore, a lot of people go for alternative therapies that help in rehabilitation of patients who suffer from cardiac stroke. The alternative therapies help in relieving pain, stress and make the body healthy and fit through exercise, yoga as well as meditation.
Those who have the cardiac complaint have to take a good care of their diet.
Also, they must look after their regular exercise in order to stay fit and make sure that they do not take undue stress. These are some of the precautions that you need to take while you are in the process of rehabilitation. The cardiac rehabilitation can be carried out at the rehabilitation centers as well as at the residence of the patients. Once the patient learns all the exercise and techniques of meditation and understands what diet he or she should include in their meals as the instructions of the doctor’s and dieticians, then it is possible to accomplish the rehabilitation process at home with little guidance and monitoring. But the best results are seen at the center, where the program is given to a group of patients together.
The alternative therapies used for cardiac rehabilitation are stress management, physical exercises and diet. Stress management is very much essential in the rehabilitation process because it has a lot of effects on the patient’s body. A lot of relaxation techniques are taught to the patients that helps them in stress management, among them meditation is one of the main focuses.
The various rehabilitation programs also give you information on how to have a stress free lifestyle. The patients are supported and encouraged to discuss their problems with the counselor or fellow patients. This helps them to vent their feelings and feel comforted. Breathing exercises are also of great help for the patients who are undergoing cardiac rehabilitation.
In addition to stress management, physical exercises are also given a lot of importance in the rehabilitation program. The patients are asked to perform various forms of physical exercise which are suitable to them depending on their age and the severity of their problems. These activities include activities like walking, jogging, cycling, and some other sports like badminton, tennis etc., to maintain their health and keep their muscles, bones, and body tissues in a good state. Cardio exercise in a gymnasium is also encouraged. This helps in strengthening the muscles and managing weight.
The diet of these patients also needs to be looked upon very carefully. Such people should stay away from alcohol and tobacco consumption in order to improve their health. Make sure that their meals include plenty of organic foodstuffs as well as fruits and juices. Do not include junk and oily foodstuffs in your diet because they are very difficult to digest. The intake of calories should also be done at required level. It is a significant fact that the patients have to understand and work accordingly.

All of the following are mentioned as the negative aspects of medical treatment EXCEPT

Iron production was revolutionized in the early eighteenth century when coke was first used instead of charcoal for refining iron ore. Previously the poor quality of the iron had restricted its use in architecture to items such as chains and tie bars for supporting arches, vaults, and walls. With the improvement in refining ore, it was now possible  to  make  cast-iron beams, columns, and girders. During the nineteenth century further advances were made, notably Bessemer’s process for converting iron into steel, which made the material more commercially viable.
Iron was rapidly adopted for the  construction  of  bridges,  because  its  strength was far greater  than that of stone or timber, but its use in the architecture of buildings developed more slowly. By 1800 a complete internal iron skeleton for buildings had been developed in industrial architecture replacing traditional timber beams, but it generally remained concealed. Apart from its low cost, the appeal of iron as a building material lay in its strength, its resistance to fire, and its potential to span vast areas. As a result, iron became increasingly popular as a structural material for more traditional styles of architecture during the nineteenth century, but it was invariably concealed.
Significantly, the use  of  exposed  iron  occurred  mainly  in  the  new  building types spawned by the Industrial Revolution: in factories, warehouses, commercial offices, exhibition hall, and railroad stations, where its  practical  advantages  far  outweighed  its  lack of status. Designers of the railroad stations of the new age explored the potential of iron, covering huge areas with spans that surpassed the great vaults of medieval churches and cathedrals. Paxton’s Crystal Palace, designed to house the Great Exhibition of 1851, covered an area of 1.848 feet by 408 feet in prefabricated units of glass set in iron frames. The Paris Exhibition of 1889 included both the widest span and the  greatest height achieved so far with the Halle Des Machines, spanning 362 feet, and the Eiffel Tower 1,000 feet high. However, these achievements were mocked by the artistic elite of Paris as expensive and ugly follies. Iron, despite its structural advantages, had little aesthetic status. The use of an exposed iron structure in the more traditional styles of architecture was slower to develop.

How did the artistic elite mentioned in the passage react to the buildings at the Paris Exhibition?

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The ocean bottom - a region nearly 2.5 times greater than the total land area of the Earth - is a vast frontier that even today is largely unexplored and uncharted. Until about a century ago, the deep ocean floor was completely inaccessible, hidden beneath waters averaging over 3,600 meters deep. Totally without light and subjected to intense pressures hundreds of times greater than at the Earth's surface, the deep-ocean bottom is a hostile environment to humans, in some ways as forbidding and remote as the void of outer space.
Although researchers have taken samples of deep-ocean rocks and sediments for over a century, the first detailed global investigation of the ocean bottom did not actually start until 1968, with the beginning of the National Science Foundation's Deep Sea Drilling Project (DSDP). Using techniques first developed for the offshore oil and gas industry, the DSDP's drill ship, the Glomar Challenger, was able to maintain a steady position on the ocean's surface and drill in very deep waters, extracting samples of sediments and rock from the ocean floor.
The Glomar Challenger completed 96 voyages in a 15-year research program that ended in November 1983. During this time, the vessel logged 600,000 kilometers and took almost 20,000 core samples of seabed sediments and rocks at 624 drilling sites around the world. The Glomar Challenger's core samples have allowed geologists to reconstruct what the planet looked like hundreds of millions of years ago and to calculate what it will probably look like millions of years in the future. Today, largely on the strength of evidence gathered during the Glomar Challenger's voyages, nearly all earth scientists agree on the theories of plate tectonics and continental drift that explain many of the geological processes that shape the Earth.
The cores of sediment drilled by the Glomar Challenger have also yielded information critical to understanding the world's past climates. Deep-ocean sediments provide a climatic record stretching back hundreds of millions of years, because they are largely isolated from the mechanical erosion and the intense chemical and biological activity that rapidly destroy much land-based evidence of past climates. This record has already provided insights into the patterns and causes of past climatic change - information that may be used to predict future climates.

The deep Sea Drilling Project was significant because it was    .

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           How the Internet Is Changing Our Language
There are words that we say today that 70 years ago weren’t even in (1)....... . If a person were to remark  to a 1950s businessman, “Go and check this website out on the Internet and get back to me via Facebook,” the businessman would have no clue as to what had just been said. We know exactly what the words mean, though, so they (2)....... perfect sense to us.
The problem that people are encountering today is the same as the 1950s businessman would have encountered - he would have  come (3).....a word that would mean nothing because he lived in a world where Internet technology is changing and progressing today at an even faster (4)........, and this is creating changes in the way we communicate. Our words are different, and even our means of (5)........those words across are different as well. Forget about a 60-plus year difference; we speak much differently than we did even 10 or 20 years ago.
(3).........................
 

Quite different from storm surges are the giant sea waves called tsunamis, which derive their name from the Japanese expression for “high water in a harbor.” These waves are also referred to by the general public as tidal waves, although they have relatively little to do with tides.
Scientists often referred to them as seismic sea waves, far more appropriate in that they do result from undersea seismic activity.
Tsunamis are caused when the sea bottom suddenly moves, during an underwater earthquake or volcano for example, and the water above the moving earth is suddenly displaced. This sudden shift of water sets off a series of waves. These waves can travel great distances at speeds close to 700 kilometers per hour. In the open ocean, tsunamis have little noticeable amplitude, often no more than one or two meters. It is when they hit the shallow waters near the coast that they increase in height, possibly up to 40 meters.
Tsunamis often occur in the Pacific because the Pacific is an area of heavy seismic activity.
Two areas of the Pacific well accustomed to the threat of tsunamis are Japan and Hawaii. Because the seismic activity that causes tsunamis in Japan often occurs on the ocean bottom quite close to the islands, the tsunamis that hit Japan often come with little warning and can, therefore, prove disastrous. Most of the tsunamis that hit the Hawaiian Islands, however, originate thousands of miles away near the coast of Alaska, so these tsunamis have a much greater distance to travel and the inhabitants of Hawaii generally have time for warning of their imminent arrival.
Tsunamis are certainly not limited to Japan and Hawaii. In 1755, Europe experienced a calamitous tsunami, when movement along the fault lines near the Azores caused a massive tsunami to sweep onto the Portuguese coast and flood the heavily populated area around Lisbon. The greatest tsunami on record occurred on the other side of the world in 1883 when the Krakatoa volcano underwent a massive explosion, sending waves more than 30 meters high onto nearby Indonesian islands; the tsunami from this volcano actually traveled around the world and was witnessed as far away as the English Channel.

It can be inferred from the passage that tsunamis ...............

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Perhaps better known than the Cullinan Diamond is the Hope Diamond, a valuable and blue gem with a background of more than 300 years as a world traveler.The 112-carat blue stone later became the Hope Diamond was mined in India sometime before the middle of the seventeenth century and was first known to be owned by Shah Jahan, who built the Taj Mahal in memory of his beloved wife. From India, the celebrated blue stone has changed hands often, moving from location to location in distant corners of the world.
In the middle of the seventeenth century, a trader from France named Jean Baptiste Tavernier acquired the large blue diamond, which was rumored to have been illegally removed from a temple Tavemier returned to France with the big blue gem, where the stone was purchased by the Sun King Louis XIV. Louis XIV had it cut down from 112 to 67 carats to make its shape symmetrical and to maximize its sparkle. The newly cut diamond, still huge by any standards, was passed down through the royal family of France, until it arrived in the hands of Louis XVI and Marie Antoinette.
During the French Revolution, Louis XVI and his wife met their fate on the guillotine in 1793, and the big blue diamond disappeared from public sight.
The diamond somehow managed to get from France to England, where banker Henry Hope purchased it from a gem dealer early in the nineteenth century. The huge blue stone was cut into a 45.5-carat oval, and at this point it took on the name by which it is known today. The diamond stayed in the Hope family for around a century, when deep indebtedness brought on by a serious gambling habit on the part of one of Henry Hope's heirs forced the sale of the diamond.
From England, the Hope Diamond may have made its way into the hands of the Sultan of Turkey; whatever route it took to get there, it eventually went on to the United States when American Evelyn Walsh McLean purchased it in 1911. Mrs.
McLean certainly enjoyed showing the diamond off guests in her home were sometimes astounded to notice the huge stone embellishing the neck of Mrs. McLean’s Great Dane as the huge pet trotted around the grounds of her Washington, D.C. home. The Hope Diamond later became the property of jeweler Harry Winston, who presented the stunning 45.5- carat piece to the Smithsonian in 1958. The Hope Diamond is now taking a well-earned rest following its rigorous travel itinerary and is on display at the Smithsonian Institution in Washington, D.C., where it has been since 1958.

The main idea of this passage is that the Hope Diamond

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There has been much debate over the past few decades concerning fears that nation will

lead to robots replacing human workers on a massive scale.

The increasing use of robotics, computers and artificial intelligence is a reality, but its full

implications are far from cut and dried. Some forecasts present the future in a utopian way,

claiming that robots will take over the tedious heavy work thus freeing up human time and

potential, allowing for more creativity and innovation,  the other end of spectrum are those who

foresee an employment apocalypse, predicting that almost fifty percent of all American jobs

could vanish within the next few decades. Former Microsoft chairman Bill Gates states that in 20

years robots could be in place in a number of job categories, particularly those at lower end of

the scale in terms of skills. The bottom line is that while the future is always uncertain, robots are a fixture of our society, which is not going to disappear. As with the Industrial Revolution, where machines were utilized in many tasks in place of manual laborers and social upheaval followed, the Digital Revolution is likely to place robots in various jobs. In spite of that, many of today's jobs were not in existence before the Industrial Revolution, such as those of programmers, engineers and data scientists. This leads other experts to criticize this alarmist approach of robot scare-mongering, which is invariably compared to the 19th -century "Luddites". This group was textile workers who feared being displaced by machines and resorted to violence, burning down factories and destroying industrial equipment - their rejection of inevitable progress has come to symbolize mindless ignorance.

Needless to say, exactly what new kinds of jobs might exist in the future is difficult to envision at present. Therefore, the crux of the issue is not whether jobs will be lost, but whether the creation of new vacancies will outpace the ever-increasing number of losses and what skills will be required in the future.

It is clearly not all doom and gloom, as demand for employees with skills in data analysis, coding, computer science, artificial intelligence and human-machine interface is rising and will continue to do so. Furthermore, the demand for skills in Jobs where humans surpass computers, such as those involving care, creativity and innovative craftmanship, are likely to increase considerably. Ultimately, the key lies in the adaptation of the workforces, through appropriate education and training, to keep pace with our world's technological progress.

What is the main idea of this article?

Before the 1500’s, the Western plains of North America were dominated by farmers. One group, the Mandans, lived in the upper Missouri River country, primarily in present-day North Dakota. They had large villages of houses built close together. The tight arrangement enabled the Mandans to protect themselves more easily from the attacks of others who might seek to obtain some of the food these highly capable farmers stored from one year to the next.
The women had primary responsibility for the fields. They had to exercise considerable skill to produce the desired results, for their northern location meant fleeting growing seasons. Winter often lingered; autumn could be ushered in by severe frost. During the spring and summer, drought, heat, hail, grasshoppers, and other frustrations might await the wary grower.
Under such conditions, Mandan women had to grow maize capable of weathering adversity. They began as early as it appeared feasible to do so in the spring, clearing the land, using fire to clear stubble from the fields and then planting. From this point until the first green corn could be harvested, the crop required labor and vigilance. Harvesting proceeded in two stages. In August the Mandans picked a smaller amount of the crop before it had matured fully. This green corn was boiled, dried, and shelled, with some of the maize slated for immediate consumption and the rest stored in animal-skin bags. Later in the fall, the people picked the rest of the corn. They saved the best of the harvest for seeds or for trade, with the remainder eaten right away or stored for later use in underground reserves. With appropriate banking of the extra food, the Mandans protected themselves against the disaster of crop failure and accompanying hunger.
The women planted another staple, squash, about the first of June, and harvested it near the time of the green corn harvest. After they picked it, they sliced it, dried it, and strung the slices before they stored them. Once again, they saved the seed from the best of the year`s crop. The Mandans also grew sunflowers and tobacco; the latter was the particular task of the older men.

Why does the author believe that the Mandans were skilled farmers?

All mammals feed their young. Beluga whale mothers, for example, nurse their calves for some twenty months, until they are about to give birth again and their young are able to find their own food. The behavior of feeding of the young is built into the reproductive system. It is a nonselective part of parental care and the defining feature of a mammal, the most important thing that mammals-- whether marsupials, platypuses, spiny anteaters, or placental mammals -- have in common.
But not all animal parents, even those that tend their offspring to the point of hatching or birth, feed their young. Most egg-guarding fish do not, for the simple reason that their young are so much smaller than the parents and eat food that is also much smaller than the food eaten by adults. In reptiles, the crocodile mother protects her young after they have hatched and takes them down to the water, where they will find food, but she does not actually feed them. Few insects feed their young after hatching, but some make other arrangement, provisioning their cells and nests with caterpillars and spiders that they have paralyzed with their venom and stored in a state of suspended animation so that their larvae might have a supply of fresh food when they hatch.
For animals other than mammals, then, feeding is not intrinsic to parental care. Animals add it to their reproductive strategies to give them an edge in their lifelong quest for descendants. The most vulnerable moment in any animal's life is when it first finds itself completely on its own, when it must forage and fend for itself. Feeding postpones that moment until a young animal has grown to such a size that it is better able to cope. Young that are fed by their parents become nutritionally independent at a much greater fraction of their full adult size. And in the meantime those young are shielded against the vagaries of fluctuating of difficult-to-find supplies. Once a species does take the step of feeding its young, the young become totally dependent on the extra effort. If both parents are removed, the young generally do not survive.

What can be inferred from the passage about the practice of animal parents feeding their young?

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Thirty years ago, Lake Ponkapog in Hartwell, New Jersey, was full of life. Many birds and animals lived beside the water, which was full of fish. Now there are few birds, animals, and fish. The lake water is polluted. It is a dirty brown colour, and it is filled with strange plants.
How did this happen? First, we must think about how water gets into Lake Ponkapog. When it rains, water comes into the lake from all around. In the past, there were woods all around Lake Ponkapog, so  the rainwater was clean.
Now there are many homes on the lake hore. People often use the chemicals in their gardens. They use other chemicals inside their houses for cleaning and killing insects. There are also many businesses. Businesses use chemicals in their machines or stores. Other chemicals fall onto the ground from cars or trucks. When it rains, the rainwater flows by these homes and businesses. It picks up all the chemicals and then pours them into the lake. They pollute the water and kill the animal life.
There is still another problem at the lake: exotic plants. These plants come from other countries. They have no natural enemies here, and they grow very quickly. In a short time, they can fill up a lake. Then there is no room for other plants. The plants that normally grow there die. These plants gave many animals and fish their foods or their homes. So now those animals and fish die, too.
People in Hartwell are worried. They love their lake and want to save it. Will it be possible? A clean lake must have clean rainwater going into it. Clean rainwater is possible only if people are more careful about chemicals at home and at work. They must also be more careful about gas and oil and other chemicals on the ground.

To save Lake Ponkapog, people need to     .

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

   Before the mid-nineteenth century, people in the United States ate most foods only in season. Drying, smoking and salting could preserve meat for a short time, but the availability of fresh meat, like that of fresh milk, was very limited; there was no way to prevent spoilage. But in 1810, a French inventor named Nicolas Appert developed the cooking-and-sealing process of canning. And in the 1850’s an American named Gail Borden developed a means of condensing and preserving milk. Canned goods and condensed milk became more common during the 1860’s, but supplies remained low because cans had to be made by hand. By 1880, however, inventors had fashioned stamping and soldering machines that massproduced cans from tinplate. Suddenly all kinds of food could be preserved and bought at all times of the year.

   Other trends and inventions had also helped make it possible for Americans to vary their daily diets. Growing urban population created demand that encouraged fruit and vegetable farmers to raise more produce. Railroad refrigerator cars enabled growers and meat packers to ship perishables great distances and to preserve them for longer periods. Thus, by the 1890’s, northern city dwellers could enjoy southern and western strawberries, grapes, and tomatoes, previously available for a month at most, for up to six months of the year. In addition, increased use of iceboxes enabled families to store perishables. As easy means of producing ice commercially had been invented in the 1870’s, and by 1900 the nation had more than two thousand commercial ice plants, most of which made home deliveries. The icebox became afixture in most homes and remained so until the mechanized refrigerator replaced it in the 1920’s and 1930’s.

   Almost everyone now had a more diversified diet. Some people continued to eat mainly foods that were heavily in starches or carbohydrates, and not everyone could afford meat. Nevertheless, many families could take advantage of previously unavailable fruits, vegetables, and dairy products to achieve more varied fare.

The word “Nevertheless” in line 19 is closest meaning to _________ .

The election of Andrew Jackson to the presidency in 1928 marked the political ascendancy of the “common man” in American politics. Whereas all previous presidents had been Easterners from well-to-do families, Jackson was a self-made man of modest wealth from the West. Born in 1767, Jackson fought in the American Revolution, in which many of his relatives died.
Afterwards, he studied law and moved to the Western District of North California. When that territory became the state of Tennessee, Jackson was elected the state’s first congressman. His name became a household word during the war of 1812, when, as a U.S Army major general, he led troops against the Creek Indians in the Mississippi Territory and later defeated the British at New Orleans.
After his presidential inauguration, Jackson rode on horseback to the White House to attend a private party. Crowds of well-wishers suddenly appeared at the reception and nearly destroyed the White House as they tried to glimpse the new president. The common man had made a dramatic entrance onto the national political scene.
Jackson’s two terms moved American society toward truer democracy. Many states abandoned property requirements for voting. Elected officials began to act more truly as representatives of the people than as their leaders. As president of the common man, Jackson waged a war against the Bank of the United States, vetoing the bill that re-chartered the institution, declaring it a dangerous monopoly that profited the wealthy few.
Although he had built his reputation as an Indian fighter during the War of 1812, Jackson was not an Indian hater. He adopted what was at the time considered an enlightened solution to the Indian problem-removal. Many tribes submitted peacefully to being moved to the West. Others were marched by force to the Indian Territory, under brutal conditions, along what the Cherokees called the Trail of Tears.
One of Andrew Jackson’s most enduring legacies was the Democratic Party, which under him became a highly organized political party. In opposition to the Democrats were the Whigs, a party that attracted supporters of the Bank of the United States and opposed the tyranny of the man called “King Andrew”. A less specific but more basic legacy is the populist philosophy of politics that still bears the name “Jacksonian Democracy.”

According to the passage, Jackson’s policy toward American Indians was ............

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
“ Calcite- containing dust particles blow into the air and combine with nitric acid in polluted air from factories to form an entirely new particle – calcium nitrate , ” said Alexander Laskin, a senior research scientist at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Washington .These nitrates have optical and chemical properties that are completely different from those of the originally dry dust particles . Due to this, climate models need to be updated to reflect this chemistry. Calcite dust is common in arid areas such as Israel, where scientists collected particles for analysis.
Working from a mountaintop, the team collected dust that had blown in from the northern shores of Egypt, Sinai,and southern Israel. The particles had combined with air containing pollutants that came from Cairo.They analyzed nearly 2,00 individual particles and observed the physical and chemical changes at the W.R Wiley Environmental Sciences Laboratory.
A key change in the properties of the newly formed nitrate particles is that they begin to absorb water and retain the moisture .These wet particles can scatter and absorb sunlight-presenting climate modelers, who need to know where the energy is going , a new wild card to deal with . Companion studies of dust samples from the Sahara and the Saudi coast and loess from China show that the higher the calcium in the mineral , the more reactive they are in with nitric acid .And once the particle is changed , it stays that way.
“When dust storms kick up these particles and they enter polluted areas , the particles change ,” Laskin said . “To what extent this is happening globally, as more of the world becomes industrialized , we don’t know . But now we have the laboratory and field evidence that shows it is definitely happening . The story is much more complicated than anybody thought .”

Do the particles react with nitric acid ?