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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 mass-produced 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 a fixture 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.
Question:The phrase “in season” in paragraph 1 refers to

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions.
She simply took it for granted that the check was good and did not ask him any questions about it.

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At first sight I met her, I was impressed with her ______ eyes.

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This is the second time you ______ your door key.

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Some methods to prevent soil erosion are plowing parallel with the slope of hills, to plant trees on unproductive land, and rotating crops.

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It is vital that everyone ______ aware of the protection of the environment.

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A smile can be observed, described, and reliably identify ; it can also be elicited and manipulated under experimental conditions.

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I love this painting of an old man. He has such a beautiful ______ smile.

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The number of higher education ______ has risen this year for the first time in more than a decade.

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It was suggested that he studies the material more thoroughly before attempting to pass the exam.

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I know we had an argument, but I know I’d quite like to ______.

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“How beautiful you are today!” he said.

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All of her sons joined the army when the war broke ______.

Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions.

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.
Satish’s point of view was correct but his behavior with his father was quite impertinent.

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

Thunderstorms, with their jagged bursts of lightning and roaring thunder, are actually one of nature’s primary mechanisms for transferring heat from the surface of the earth into the atmosphere. A thunderstorm starts when low-lying pockets of warm air from the surface of the earth begin to rise. The pockets of warm air float upward through the air above that is both cooler and heavier. The rising pockets cool as their pressure decreases, and their latent heat is released above the condensation line through the formation of cumulus clouds.

What will happen with these clouds depends on the temperature of the atmosphere. In winter, the air temperature differential between higher and lower altitudes is not extremely great, and the temperature of the rising air mass drops more slowly. During these colder months, the atmosphere, therefore, tends to remain rather stable. In summer, however, when there is a high accumulation of heat near the earth’s surface, in direct contrast to the considerably colder air higher up, the temperature differential between higher and lower altitudes is much more pronounced. As warm air rises in this type of environment, the temperature drops much more rapidly than it does in winter; when the temperature drops more than 4 degrees Fahrenheit per thousand feet of altitude, cumulus clouds aggregate into a single massive cumulonimbus cloud, or thunderhead.

In isolation, a single thunderstorm is an impressive but fairly benign way for Mother Earth to defuse trapped heat from her surface; thunderstorms, however, can appear in concert, and the resulting show, while extremely impressive, can also prove extraordinarily destructive. When there is a large-scale collision between cold air and warm air masses during the summer months, a squall line, or series of thunderheads, may develop. It is common for a squall line to begin when an advancing cold front meets up with and forces itself under a layer of warm and moist air, creating a line of thunderstorms that races forward at speeds of approximately forty miles per hour. A squall line, which can be hundreds of miles long and can contain fifty distinct thunderheads, is a magnificent force of nature with incredible potential for destruction. Within the squall line, often near its southern end, can be found supercells, long-lived rotating storms of exceptional strength that serve as the source of tornadoes.
Question:The topic of the passage is ________.