Choose the best answer:
Robots in factories will be able to do everything the workers do, __________ robots will make them jobless.

Thanks for a great year! In case you haven't heard, Henwith Home Supply will be ---135--- our second store this spring. This additional retail site will be located in the shopping centre at the corner of Aberton Parkway and Sutton Avenue in Derbyshire.

We will be accepting applications for cashiers and sales position
---136--- 1 April. The personnel director will review applicants' qualifications from 2 April to 6 April, and ---137--- is scheduled to begin one week later.---138---.

136.................

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:
Generally, in order to be preserved in the fossil record, organisms must possess hard body parts such as shells or bones. Soft, fleshy structures are quickly destroyed by predators or decayed by bacteria. Even hard parts left on the surface for any length of time will be destroyed, therefore, organisms must be buried rapidly to escape destruction by the elements and to be protected against agents of weathering and erosion. Marine organisms thus are better candidates for fossilization than those living on the land because the ocean is typical the site of sedimentation, whereas the land is largely the site of erosion. The beds of ancient lakes were also excellent sites for rapid burial of skeletal remains of freshwater organisms and skeletons of other animals, including those of early humans, Ancient swaps were  particularly plentiful with prolific growths of vegetation, which fossilized in abundance. Many animals became trapped in bogs overgrown by vegetation. The environment of the swaps kept bacterial decay to a minimum, which greatly aided in the preservation of plants and animals. The rapidly accumulating sediments in flood plains, deltas, and stream channels buried freshwater organisms, along with other plants and animals that happened to fall into the water.
Only a small traction of all the organisms that have ever lived are preserved as fossils. Normally, the remains of a plant or animal are completely destroyed through predation and decay. Although it seems that fossilization is common for some organisms, for others it is almost impossible. For the most part of, the remains of organisms are recycled in the earth, which is fortunate because otherwise soil and water would soon became depleted of essential nutrients. Also, most of the fossils exposed on Earth’s surface are destroyed by weathering processes. This make for an incomplete fossil record with poor or no representation of certain species. The best fossils are those composed of that form the vast majority of unaltered fossils. Calcite and aragonite also contributed to a substantial number of fossils of certain organisms.

According to the passage, an organisms without hard body parts     

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:
U.N. diplomats abandoned efforts to draft a treaty that would outlaw human cloning. They will likely settle for a weaker statement, and won’t seek a widespread ban, officials said. The debate began when Italy introduced a document into the UN. to stop any attempt at cloning human life. The Belgians objected to the use of the term “human life” in the document, because they feared it would put a stop to all forms of human cloning.
[1] There is near universal support among the United Nations’ 191 members for a ban on reproductive cloning-creating cloned babies. [2] Many countries have wrestled over whether to allow cloning for stem cell and other types of research. [3] Indeed, many researchers believe that stem cells could be used to repair nerve tissue or cure diseases, including Alzheimer’s. [4] Stem cells are taken from embryos and cloned, but extracting these cells kills the embryo. Opponents say that this is equal to murder.

The word “it” in-the text refers 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:
The diary and the letter were the most extensively practiced forms of life writings in eighteenth- century America. From the numerous examples of these two types of writing from the period, a portrait of daily life of the period can be gleaned.
Many of the diaries that were kept during this period were life diaries by authors interested in maintaining day-to-day records of reflective self-examination, but some of the most compelling were situational diaries; those prompted by and limited to lengthy descriptions of personal reflections about a particular event. Three of the many situational journals of this period are those written by Sarah Kemble Knight, William Burd II, and Dr. Alexander Hamilton. Sarah Kemble Knight's diary of her five-month trip at the end of 1704 and the beginning of 1705 from Boston to New Haven to New York and back again to Boston was published more than a century later as The Journal of Madam Knight. Though this diary does include an account of the hardship that she encountered along the way, it is principally composed of humorous descriptions of and commentary on the hospitality that she was offered and the manners of those that she encountered. William Burd II kept two diaries to describe his experiences on a 1729 surveying expedition to settle a border dispute between Virginia and North Carolina. One of the diaries, History of the Dividing Line between Virginia and North Carolina, was published in 1842, while its companion, Secret Diary, was published in 1929. In these diaries, Burd used a humorous and satirical approach to describe not just the day-to-day events of the trip but also the characteristics which set his beloved Virginia culture apart from the (in his opinion) decidedly less praiseworthy culture of those non- Virginians that he encountered in his trip. Dr. Alexander Hamilton's Itinerarium (1744) describes a four- month voyage of discovery undertaken by Hamilton through the mid-Atlantic and New England colonies; in the diary that he kept of this trip. Hamilton provides considerable commentary on the social customs of various areas, comparing the customs and culture of the better homes of the American colonies with those of the great salons of Europe.
Letter-writing also held a place of importance in eighteenth-century America (indeed, the ability to produce cultured letters was considered a form of art), and many letters extant from that period provide insights into the culture, mores, and styles of written communication of that era. Many of the letter writers employed devices in common usage in European models of the time, demonstrating that letter writers felt a sense of cohesiveness with the cultured classes of Europe: John and Abigail Adams signed the names Lysander and Constantia to their early letters, while Thomas Jefferson created an elaborate dialogue between his head and his heart to discuss the nature of friendship in  a 1786 letter to Maria Cosway. The variety of purposes that these letters served provides additional insight into the priorities of the society of the time. The letters were used to cement love matches and friendships, as the previously mentioned letters did; they were the primary method for relaying news among family and friends who were scattered across various geographic locations; they were often used as a means of carrying out business in this era before more rapid long-distance communication; they were often used used as a way of sharing professional, social, or political ideas among leaders in various fields who perhaps had no other way to get together and exchange ideas.

What is stated in the passage about the works by Knight, Burd, and Hamilton?

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:
During the second half of the nineteenth century, the production of food and feed crops in the United States rose at an extraordinarily rapid rate. Com production increased by four and a half times, hay by five times, oats and wheat by seven times. The most crucial factor behind this phenomenal upsurge in productivity was the widespread adoption of labor-saving machinery by northern farmers. By 1850 horse- drawn reaping machines that cut grain were being introduced into the major grain-growing regions of the country. Horse-powered threshing machines to separate the seeds from the plants were already in general use. However, it was the onset of the Civil War in 1861 that provided the great stimulus for the mechanization of northern agriculture. With much of the labor force inducted into the army and with grain prices on the rise, northern farmers rushed to avail themselves of the new labor-saving equipment. In 1860 there were approximately 80,000 reapers in the country; five years later there were 350,000.
After the close of the war in 1865, machinery became ever more important in northern agriculture, and improved equipment was continually introduced. By 1880 a self-binding reaper had been perfected that not only cut the grain, but also gathered the stalks and bound them with twine. Threshing machines were also being improved and enlarged, and after 1870 they were increasingly powered by steam engines rather than by horses. Since steam-powered threshing machines were costly items-running from $ 1,000 to $4,000 - they were usually owned by custom thresher owners who then worked their way from farm to farm during the harvest season. “Combines” were also coming into use on the great wheat ranches in California and the Pacific Northwest. These ponderous machines - sometimes pulled by as many as 40 horses - reaped the grain, threshed it, and bagged it, all in one simultaneous operation.
The adoption of labor-saving machinery had a profound effect upon the sale of agricultural operations in the northern states-allowing farmers to increase vastly their crop acreage. By the end of century, a farmer employing the new machinery could plant and harvest two and half times as much com as a farmer had using hand methods 50 years before.

What aspect of farming in the United States in the nineteenth century does the passage mainly discuss?

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.

   Martin Luther King, Jf., is well- known for his work in civil rights and for his many famous speeches, among which 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 purchased their home on Auburn Avenue in 1909, twenty years before M.L was born. His grandfather allowed the house 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 the 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 eventfully. 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 an area of banks, insurance companies, builders, jewelers, tailors, doctors, lawyers, and other 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 huge barrier keeping black Atlantans from mingling with whites.

M.L. was _______ by the atmosphere in which he grew up.

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Around 365 B.C. in ancient Greece, the great teacher Plato told a story about a place called Atlantis. Plato described Atlantis as a continent in the Atlantic Ocean. He said it had been the home of a powerful people who were destroyed when the continent was swallowed by the sea.
Ever since Plato’s time, people have wondered if the story about Atlantis was really true. Was there ever such a place as Atlantis? During the Middle Ages, many people believed in the legend of Atlantis. Some men even made voyages to find the “lost continent”. Later, most people believed Atlantis to be just a myth. Scientists could find no evidence to show that such a place had ever existed.
Ideas change in time, however, for now some scientists think that Atlantis might have been a real place. A Greek professor has offered a new theory. He says that Atlantis was not a continent in the Atlantic Ocean but an island called Thera in the Aegean Sea. The professor says that 3,500 years ago much of Thera collapsed into the sea when a volcano erupted. He thinks that before the explosion Thera had been the home of a people called Minoans. The Minoans were sea traders who ruled the Aegean Sea from 2,000
B.C. to 1,250 B.C.
Scientist who have come to investigate Thera have found an ancient city buried beneath volcanic ash and stone. It appears that the people who lived in the city had an advanced civilization. They were probably Minoans.
Is Thera the “lost continent” of Atlantis? No one may ever know for certain. Atlantis may remain a riddle without an answer.

A lot of people in the Middle Ages .

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 texting pigeons
Not everybody recognizes the benefits of new developments in communnicatons technology. Indeed, some people fear that text messaging may actually be having a negative (11).....on your people’s communication and language skills, especially when we hear that primary school children may be at rick of becoming addicted to the habit. So widespread has texting become, however, that even pigeons have started doing it. (12)........ , in this case, it’s difficult to view the results as anything but positive.
Twenty of the birds are about to take to the skies with the task of measuring air pollution, each (13)................with sensor equipment and a mobile phone. The readings made by the sensors will be automatically converted into text messages and beamed to the Internet – (14)...............they will appear on a dedicated ‘pigeon blog’. The birds will also each have a GPS receiver and a camera to capture aerial photos, and researchers are building a tiny ‘pigeon kit’ containing all these gadgets. Each bird will carry these in a miniature backpack, (15)............ , that is, from the camera, which will hang around its neck.
 The data the pigeons text will be displayed in the form of an interactive map, which will provide local residents with up-to-the-minute information on thir local air quality.(11)....................

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.
Christina and James met in college and have been dating for more than five years. For the  past two years, they have been living together in a  condo  they  purchased jointly. While Christina and James were confident in their decision to enter into a commitment like a  20-year mortgage,  they are unsure if they want to enter into marriage. The couple had many discussions about marriage and decided that it just did not seem necessary. Wasn't it only a piece of  paper? And  didn't half of all marriages end in divorce?
Neither Christina nor James had seen much success with marriage while growing up. Christina was raised by a single mother. Her parents never married, and her father has had little contact with the family since she was a toddler, Christina and her mother lived with her maternal grandmother, who often served as a surrogate parent. James grew up in  a  two-parent household  until age seven, when his parents divorced. He lived with his mother for a  few years, and then    later with his mother and her boyfriend until he left for college. James remained close with his  father who remarried and had a baby with his new wife.
Recently, Christina and James have been thinking about having children and the subject of marriage has resurfaced. Christina likes the idea of her children growing up in a traditional  family; while James is concerned about possible marital problems down the road and negative consequences for the children should that occur. When they shared these concerns with their parents, James's mom was adamant that the couple should get married. Despite having been divorced and having a live-in boyfriend of 15  years, she believes that children are better off when  their parents are married. Christina's mom believes that the couple should do whatever they want but adds that it would "be nice" if they wed. Christina and James's friends told them, married or not married; they would still be a family.

What is the advice of the couple's parents?

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In 1900 the United States had only three cities with more than a million residents-New York, Chicago, and Philadelphia. By 1930, it had ten giant metropolises. The newer ones experienced remarkable growth, which reflected basic changes in the economy. The population of Los Angeles (114,000 in 1900) rose spectacularly in the early decades of the twentieth century, increasing a dramatic 1,400 percent from 1900 to 1930.
A number of circumstances contributed to the meteoric rise of Los Angeles. The agricultural potential of the area was enormous if water for irrigation could be found, and the city founders had the vision and dating to obtain it by constructing a 225-mile aqueduct, completed in 1913, to tap the water of the Owens River. The city had a superb natural harbor, as well as excellent rail connections. The climate made it possible to shoot motion pictures year-round; hence Hollywood not only supplied jobs but also disseminated an image of the good life in Southern California on screens all across the nation. The most important single industry powering the growth of Los Angeles, however, was directly linked to the automobile. The demand for petroleum to fuel gasoline engines led to the opening of the Southern California oil fields, and made Los Angeles North America’s greatest refining center.
Los Angeles was a product of the auto age in another sense as well: its distinctive spatial organization depended on widespread private ownership of automobiles. Los Angeles was a decentralized metropolis, sprawling across the desert landscape over an area of400 square miles.
It was a city without a real center. The downtown business district did not grow apace with the city as a whole, and the rapid transit system designed to link the center with outlying areas withered away from disuse. Approximately 800,000 cars were registered in Los Angeles County in 1930, one per 2.7 residents. Some visitors from the east coast were dismayed at the endless urban sprawl and dismissed Los Angeles as a mere collection of suburbs in search of a city. But the freedom and mobility of a city built on wheels attracted floods of migrants to the city.

The visitors from the east coast mentioned in the passage thought that Los Angeles

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:
In 1900 the United States had only three cities with more than a million residents-New York, Chicago, and Philadelphia. By 1930, it had ten giant metropolises. The newer ones experienced remarkable growth, which reflected basic changes in the economy. The population of Los Angeles (114,000 in 1900) rose spectacularly in the early decades of the twentieth century, increasing a dramatic 1,400 percent from 1900 to 1930.
A number of circumstances contributed to the meteoric rise of Los Angeles. The agricultural potential of the area was enormous if water for irrigation could be found, and the city founders had the vision and dating to obtain it by constructing a 225-mile aqueduct, completed in 1913, to tap the water of the Owens River. The city had a superb natural harbor, as well as excellent rail connections. The climate made it possible to shoot motion pictures year-round; hence Hollywood not only supplied jobs but also disseminated an image of the good life in Southern California on screens all across the nation. The most important single industry powering the growth of Los Angeles, however, was directly linked to the automobile. The demand for petroleum to fuel gasoline engines led to the opening of the Southern California oil fields, and made Los Angeles North America’s greatest refining center.
Los Angeles was a product of the auto age in another sense as well: its distinctive spatial organization depended on widespread private ownership of automobiles. Los Angeles was a decentralized metropolis, sprawling across the desert landscape over an area of400 square miles.
It was a city without a real center. The downtown business district did not grow apace with the city as a whole, and the rapid transit system designed to link the center with outlying areas withered away from disuse. Approximately 800,000 cars were registered in Los Angeles County in 1930, one per 2.7 residents. Some visitors from the east coast were dismayed at the endless urban sprawl and dismissed Los Angeles as a mere collection of suburbs in search of a city. But the freedom and mobility of a city built on wheels attracted floods of migrants to the city.

The word “meteoric" in the second paragraph is closest in meaning 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:
Dark matter in the universe is believed by some scientists to be a substance that is not readily observable because it does not directly refract light or energy. Its existence can only be deduced because of the effect that it has on surrounding matter. In fact, some members of the scientific community have argued that dark matter does not actually exist. Others, however, believe in its existence, in part because the scientific community does not have a complete understanding of gravita science. On the other hand, some would argue that it is the understanding of gravitational science that leads most scientists to believe in the existence of dark matter, because without dark matter, there are many cosmological phenomena
that are difficult to explain.
For example, dark matter in the universe may have a peculiar effect on the Milky Way galaxy. Some scientists believe that the interaction between dark matter and other smaller, nearby galaxies is causing the Milky Way galaxy to take on a warped profile. It has been asserted that not only does dark matter exist, it may also be responsible for the Milky Way’s unusual shape. The interaction referenced involves two smaller galaxies near the Milky Way, called Magellanic clouds, moving through an enormous amount of dark matter, which, in effect, enhances the gravitational pull that the two Magellanic clouds could have on the Milky Way and other surrounding bodies. Without the existence of the dark matter, the Magellanic clouds would not have sufficient mass to have such a strong effect on the bend of the Milky Way galaxy.
The strongest evidence for the validity of this hypothesis rests in Newtonian physics, and the hypothesis that anything with mass will exert a gravitational pull. The Milky Way and other galaxies with peculiar warped shapes are being molded by a gravitational force. However, there is nothing readily observable with sufficient mass that could cause such a high level of distortion via gravitational pull in the vicinity of the Milky Way. Therefore, something that is not easily observed must be exerting the necessary force to create the warped shape of the galaxy.
Aaron Romanowsky and several colleagues have questioned the effect that dark matter might have on galaxies. They point to the existence of several elliptical galaxies surrounded by very little dark matter as evidence that dark matter is not, in fact, the cause of the warped galaxies. While they do not claim that their findings should be interpreted to conclude that dark matter does not exist, they apparently believe that the results of their studies cast doubt on some of the conventional theories of galaxy formation and manipulation.
Several models constructed by researchers from the University of California at Berkeley, however, point to the idea that dark matter is the most likely explanation for the distorted shape of the Milky Way and other galaxies. Using computer models, they have mapped the likely interactions between certain galaxies and the surrounding dark matter, and those models have shown not only the possibility that dark matter is responsible for the warped shape of the Milky Way, but that the relationship between the dark matter and the Magellanic clouds is dynamic; the movement of the clouds through the dark matter seems to create a wake that enhances their gravitational influence on the Milky Way.

The last paragraph supports the general hypothesis provided earlier in the passage that:

Lakeview Railway Onboard Bicycle Policy

Would you like to use your bicycle to explore the Lakeview Corridor Scenic Area? Our trains have the ---131--- you need to safety transport your bike. When booking your ticket, just remember that reservations ---132--- for both you and your bicycle. Reserve your bicycle spot-----133---. There are a limited number of storage racks on each train. You are responsible for stowing your bike securely.
---134---. Lakeview Railway does not take responsibility for bicycles lost or damaged aboard our trains.

131................

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:
Dark matter in the universe is believed by some scientists to be a substance that is not readily observable because it does not directly refract light or energy. Its existence can only be deduced because of the effect that it has on surrounding matter. In fact, some members of the scientific community have argued that dark matter does not actually exist. Others, however, believe in its existence, in part because the scientific community does not have a complete understanding of gravita science. On the other hand, some would argue that it is the understanding of gravitational science that leads most scientists to believe in the existence of dark matter, because without dark matter, there are many cosmological phenomena
that are difficult to explain.
For example, dark matter in the universe may have a peculiar effect on the Milky Way galaxy. Some scientists believe that the interaction between dark matter and other smaller, nearby galaxies is causing the Milky Way galaxy to take on a warped profile. It has been asserted that not only does dark matter exist, it may also be responsible for the Milky Way’s unusual shape. The interaction referenced involves two smaller galaxies near the Milky Way, called Magellanic clouds, moving through an enormous amount of dark matter, which, in effect, enhances the gravitational pull that the two Magellanic clouds could have on the Milky Way and other surrounding bodies. Without the existence of the dark matter, the Magellanic clouds would not have sufficient mass to have such a strong effect on the bend of the Milky Way galaxy.
The strongest evidence for the validity of this hypothesis rests in Newtonian physics, and the hypothesis that anything with mass will exert a gravitational pull. The Milky Way and other galaxies with peculiar warped shapes are being molded by a gravitational force. However, there is nothing readily observable with sufficient mass that could cause such a high level of distortion via gravitational pull in the vicinity of the Milky Way. Therefore, something that is not easily observed must be exerting the necessary force to create the warped shape of the galaxy.
Aaron Romanowsky and several colleagues have questioned the effect that dark matter might have on galaxies. They point to the existence of several elliptical galaxies surrounded by very little dark matter as evidence that dark matter is not, in fact, the cause of the warped galaxies. While they do not claim that their findings should be interpreted to conclude that dark matter does not exist, they apparently believe that the results of their studies cast doubt on some of the conventional theories of galaxy formation and manipulation.
Several models constructed by researchers from the University of California at Berkeley, however, point to the idea that dark matter is the most likely explanation for the distorted shape of the Milky Way and other galaxies. Using computer models, they have mapped the likely interactions between certain galaxies and the surrounding dark matter, and those models have shown not only the possibility that dark matter is responsible for the warped shape of the Milky Way, but that the relationship between the dark matter and the Magellanic clouds is dynamic; the movement of the clouds through the dark matter seems to create a wake that enhances their gravitational influence on the Milky Way.

The word “they” in paragraph 5 refers to:

Read the following passage and mark A, B, C, or D to indicate the correct answer to each of the blanks.
Global warming is the current increase in temperature of the Earth’s surface (both land and water) as well as its atmosphere. Average temperature around the world have risen by 0.75°C (1.4°F) (1)....... the last 100 years. About two thirds of this increase has occured since 1975 in the past, when the Earth experienced increases in temperature it was the result of natural causes, but today it is being caused by accumulation of greenhouse gases in the atmosphere produced by human(2)........... .
The natural greenhouse effect maintains the Earth’s temperature at a safe level making it (3)...............for humans and many other life forms to exist. However, since The Industrial Revolution what benefits human has significantly enhanced the greenhouse effect (4)............ the Earth’s average temperature to rise by almost 1°C. This is creating the global warming (5)..............we see today

(3)...................................

For the last three years we have charged the same wholesale prices for our baked goods, including cakes, pies, cookies, and brownies. We regret that sharply rising prices for our raw ingredients, such as sugar and fruit, have forced us to raise our prices by 5 percent ---135--- August 1. We have made every attempt to avoid this price increase. ---136---, we refuse to compromise on the quality of our products. Using the best ingredients available will allow us to provide the delicious desserts your restaurant guests have come to expect. -------137---.We appreciate your ---138--- and look forward to continuing to serve you.

135................

I am delighted to inform you that Voyacon has been selected as one of this year’s Code Touch Magazine’s Top 25 Emerging Technology Firms. We will be ---139--- your company in our September issue. This is considered a great honor by our readers, as our list includes only ---140--- that advance the industry in significant ways.

As Voyacon’s founder, could you e-mail us a digital photograph of yourself to use in the article?---141---. We could need to receive it ---142--- August 5. Otherwise, we will use a public-domain photo. Thanks for your help, and congratulations.

139....................

Choose the best answer:
Every student is worried _______ the upcoming examination.

Choose the best answer:
Thomas Edison was one of the greatest __________ of the world.

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:
Many of the most damaging and life-threating types of weather-torrential rains, severe thunderstorms, and tornadoes-begin quickly, strike suddenly, and dissipate rapidly, devastating small regions while leaving neighboring areas untouched. One such event, a tornado, struck the northeastern section of Edmonton, Alberta, in July 1987. Total damages from the tornado exceeded $250 million, the highest ever for any Canadian storm. Conventional computer models of the atmosphere have limited value in predicting short-live local storms like the Edmonton tornado, because the available weather data are generally not detailed enough to allow computers to discern the subtle atmospheric changes that precede these storms. In most nations, for example, weather balloon observations are taken just once every twelve hours at locations typically separated by hundreds of miles. With such limited data, conventional forecasting models do a much better job predicting general weather conditions over large regions than they do forecasting specific local events.
Until recently, the observation-intensive approach needed for accurate, very short range forecasts, or “Nowcasts”, was not feasible. The cost of equipping and operating many thousands of conventional weather stations was prohibitively high, and the difficulties involved in rapidly collecting and processing the raw weather data from such a network were insurmountable. Fortunately, scientific and technological advances have overcome most of these problems. Radar systems, automated weather instruments, and satellites are all capable of making detailed, nearly continuous observation over large regions at a relatively low cost. Communications satellites can transmit data around the world cheaply and instantaneously, and modern computers can quickly compile and analyzing this large volume of weather information. Meteorologists and computer scientists now work together to design computer programs and video equipment capable of transforming raw weather data into words, symbols, and vivid graphic displays that forecasters can interpret easily and quickly. As meteorologists have begun using these new technologies in weather forecasting offices, Nowcasting is becoming a reality.

Why does the author state that observations are taken “just once every twelve hours”?