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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 Development of Refrigeration Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses. Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled. Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vaporcompression refrigeration to the brewing and meatpacking industries. Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines. The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone. What is the main reason that people developed methods of refrigeration?
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 following questions The economic expansion prompted by the Second World War triggered a spectacular population boom in the West. Of course, the region was no stranger to population booms. Throughout much of its history, western settlement had been characterized by spurts, rather than by a pattern of gradual and steady population growth, beginning with the gold and silver rushes of the 1850's and 1860's. The decade after the First World War - the 1920's - witnessed another major surge of people pouring into the West, particularly into urban areas. But the economic depression of the 1930's brought this expansion to a halt; some of the more sparsely settled parts of the region actually lost population as migrants sought work in more heavily industrialized areas. By 1941 when the United States entered the Second World War and began to mobilize, new job opportunities were created in the western part of the nation. If the expansion of industries, such as shipbuilding and aircraft manufacturing, was most striking on the pacific coast, it also affected interior cities like Denver, Phoenix, and Salt Lake City. Equally dramatic were the effects of the establishment of aluminum plants in Oregon and Washington and the burgeoning steel industry in Utah and California. The flow of people into these areas provided an enormous impetus to the expansion of the service industries - banks, health care services and schools. Although strained to the limit by the influx of newcomers, western communities welcomed the vast reservoir of new job opportunities. At the same time, the unprecedented expansion of government installations in the West, such as military bases, created thousands of new civilian openings. As land had served as a magnet for western migrants in the late nineteenth century, so wartime mobilization set in motion another major expansion of population. Indeed, it could be said that the entire western United States became a giant boomtown during the Second World War. This was especially true of California. Of the more than eight million people who moved into the West in the decade after 1940, almost one-half went to the Pacific coast. In fact, between 1940 and 1950, California's population surged by more than three million people. What is the main point of the passage?
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 following questions Ranked as the number one beverage consumed worldwide, tea takes the lead over coffee in both popularity and production with 5 million metric tons of tea produced annually. Although much of this tea is consumed in Asian, European and African countries, the United States drinks its fair share. According to estimates by the Tea Council of the United States, tea is enjoyed by no less than half of the U.S population on any given day. Black tea or green tea – iced, spiced or instant – tea drinking has spurred a billion-dollar with major tea producer in Africa and South America and throughout Asia. Tea is made from the leaves from an evergreen plant, Camellia saneness, which grows tall and lush in tropical region. On tea plantation, the plant is kept trimmed to approximately four feet high and as new buds called flush appear; they are plucked off by hand. Even in today’s world of modern agricultural machinery, hand harvesting continues to be the preferred method. Ideally, only the top two leaves and a bud should be picked. This new growth produces the highest quality tea. After being harvested, tea leaves are laid out on long drying racks, called withering racks, for 18 to 20 hours. During this process, the tea softens and become limp. Next, dependent on the type of tea being product, the leaves may be crushed or chopped to release flavor, and then fermented under controlled condition of heat and humidity. For green tea, the whole leaves are often steamed to retain their green color, and the fermentation process is skipped. Producing black teas requires fermentation during which the tea leaves begin darken. After fermentation, black tea is dried in vats to produce its rich brown or black color. No one knows when or how tea became popular, but legend has it that tea as a beverage was discovered in 2737 B.C. by Emperor Shen Nung of China when leaves from camellia dropped into his drinking water as it was boiling over a fire. As the story goes, Emperor Shen Nung drank the resulting liquid and proclaimed that the drink to be most nourishing and refreshing. Though this account cannot be documented, it is thought that tea drinking probably originated in China and spread to other parts of Asia, then Europe, and ultimately to America colonies around 1650. With about half the caffeine content of coffee, tea is often chosen by those who want to reduce, but not necessarily eliminate their caffeine intake. Some people find that tea is less acidic than coffee and therefore easier on the stomach. Others have become interested in tea drinking since the National Cancer Institute publishes its finding on the antioxidant properties of tea. But whether tea is enjoyed for it perceived health benefit, its flavor, or as a social drink, teacups continue to be filled daily with the world’ most popular beverage. According to the passage, what is implied about tea harvesting?
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 following questions Each person has different learning preferences and styles that benefit them. Some may find they have a dominant learning style. Others prefer different learning styles in different circumstances. There is no right or wrong answer to which learning style is best for you - or mix of learning styles. However, by discovering and better understanding your own learning styles, you can employ techniques that will improve the rate and quality of your learning. If you prefer lessons that employ images to teach, you are a visual learner. Visual learners retain information better when it is presented in pictures, videos, graphs and books. They frequently draw pictures or develop diagrams when trying to comprehend a subject or memorize rote information. If you are a visual learner, use pictures, images, color, diagrams and other visual media in your note taking, test preparation and studying. Whenever possible, use pictures instead of text. Try to develop diagrams to comprehend concepts and storyboards to remember important sequences and relationships. Aural (auditory) learners retain information better when it’s presented in lecture format, via speeches, audio recordings, and other forms of verb communication. While a visual learner would prefer to read a book or watch a video, auditory learners would prefer to attend a lecture or listen to a book on tap. Aural learners are also big on sound and music. They can typically sing, play an instrument and identify different sounds. If you are an aural learner, integrate auditory media, listening techniques, sound, rhyme, or even music in your learning and studying. You may also consider using background music and sounds to help you with visualization of processes and systems. For example, if you’re practicing fight procedures, you may consider playing a recording of an aircraft in the background as you study. Replacing the lyrics of a favorite song with information you are learning is a very powerful way to memorize large amounts of information for aural learning. Use this technique and you will never forget the information again.  What does the passage mainly discuss?