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.
Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.
For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.
What is true of Pfiesteria?
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1. Thông tin: Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida.
Đáp án: ARead 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.
These stories of killer bees in the news in recent years have attracted a lot of attention as the bees have made their way from South America to North America. Killer bees are reputed to be extremely aggressive in nature, although experts say that their aggression may have been somewhat inflated. The killer bee is a hybrid- or combination- of the very mild European strain of honeybee and the considerably more aggressive African bee, which was created when the African strain was imported into Brazil in 1955. The African bees were brought into Brazil because their aggression was considered an advantage: they were far more productive than their European counterparts in that they spent a higher percentage of their time working and continued working longer in inclement weather than did the European bees. These killer bees have been known to attack humans and animals, and some fatalities have occurred. Experts point out, however, that the mixed breed known as the killer bee is actually not at all as aggressive as the pure African bee. They also point out that the attacks have a chemical cause. A killer bee stings only when it has been disturbed; it is not aggressive by nature. However, after a disturbed bee stings and flies away; it leaves its stinger embedded in the victim. In the viscera attached to the embedded stinger is the chemical isoamyl acetate, which has an odor that attracts other bees. As other bees approach the victim of the original sting, the victim tends to panic, thus disturbing other bees and causing them to sting. The new stings create more of the chemical isoamylacetate which attracts more bees and increases the panic level of the victim. Killer bees tend to travel in large clusters or swarms and thus respond in large numbers to the production of isoamyl acetate.
The subject of the preceding paragraph was most likely
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
Our demand for water is constantly increasing. Every year there are more and more people in the world. Factories turn out more and more products and need more and more water. We live in a world of water. But almost all of it – about 97%-is in the oceans. This water is too salty to be used for drinking, farming, and manufacturing. Only about 3% of the world’s water is fresh. Most of this water is not easily available to man because it is locked in glaciers and icecaps. There is as much water on earth today as there ever was or will ever be. Most of the water we use finds its way to the oceans. There, it is evaporated by the sun. It then falls back to the earth as rain. Water is used and reused over again. It is never used up. Although the world as a whole has plenty of fresh water, some regions have a water shortage. Rain does not fall evenly over the earth. Some regions are always too dry, and others too wet. A region that usually gets enough rain may suddenly have a serious dry spell and another region may be flooded with too much rain.
All of the following statements can be inferred from the text EXCEPT
Mark the letter A, B, C, D to indicate the word(s) CLOSEST in meaning to the underlined word(s)
The older generation is likely to be proud of the younger generation’s prowess in technology rather than to view it as a problem.
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
Successful students often do the followings while studying. First, they have an overview before reading. Next, they look for important information and pay greater attention to it (which often needs jumping forward or backward to process information). They also relate important points to one another. Also, they activate and use their prior knowledge. When they realize that their understanding is not good, they do not wait to change strategies. Last, they can monitor understanding and take action to correct or “fix up” mistakes in comprehension.
Conversely, students with low academic achievement often demonstrate ineffective study skills. They tend to assume a passive role, in learning and rely on others (e.g., teachers, parents) to monitor their studying, for example, low-achieving students often do not monitor their understanding of content; they may not be aware of the purpose of studying; and they show little evidence of looking back, or employing “fix-up” strategies to fix understanding problems. Students who struggle with learning new information seem to be unaware that they must extent effort beyond simply reading the content to understand and remember it. Children with learning disabilities do not plan and judge the quality of their studying. Their studying may be disorganized. Students with learning problems face challenges with personal organization as well. They often have difficulty keeping track of materials and assignments, following directions, and completing work on time. Unlike good studiers who employ a variety of study skills in a flexible yet purposeful manner, low-achieving students use a restricted range of study skills. They cannot explain why good study strategies are important for learning; and they tend to use the same, often ineffective study approach for all learning tasks, ignoring task content, structure or difficulty.
What is the topic of the passage?
