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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. Though Edmund Halley was most famous because of his achievements as an astronomer, he was a scientist of diverse interests and great skill. In addition to studying the skies, Halley was also deeply interested exploring the unknown depths of the oceans. One of his lesser-known accomplishments that was quite remarkable was his design for a diving bell that facilitated exploration of the watery depths.The diving bell that Halley designed had a major advantage over the diving bells that were in use prior to his. Earlier diving bells could only make use of the air contained within the bell itself, so divers had to surface when the air inside the bell ran low. Halley's bell was an improvement in that its design allowed for an additional supply of fresh air that enabled a crew of divers to remain underwater for several hours.The diving contraption that Halley designed was in the shape of a bell that measured three feet across the top and five feet across the bottom and could hold several divers comfortably; it was open at the bottom so that divers could swim in and out at will. The bell was built of wood, which was first heavily tarred to make it water repellent and was then covered with a half-ton sheet of lead to make the bell heavy enough to sink in water. The bell shape held air inside for the divers to breathe as the bell sank to the bottom.The air inside the bell was not the only source of air for the divers to breathe, and it was this improvement that made Halley's bell superior to its predecessors. In addition to the air already in the bell, air was also supplied to the divers from a lead barrel that was lowered to the ocean floor close to the bell itself. Air flowed through a leather pipe from the lead barrel on the ocean floor to the bell. The diver could breath the air from a position inside the bell, or he could move around outside the bell wearing a diving suit that consisted of a lead bell-shaped helmet with a glass viewing window and a leather body suit, with a leather pipe carrying fresh air from the diving bell to the helmetThe expression ran low in paragraph 2 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 following questions from 22 to 28.An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled - a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of the health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions.Many of the more important air pollutants, such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentration of these pollutants was altered by various chemical reactions; they became components in biogeochemical cycles. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil. On a global basis, nature's output of these compounds dwarfs that resulting from human activities.However, human production usually occurs in a localized area, such as a city. In such a region, human output may be dominant and may temporarily overload the natural purification scheme of the cycles. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact, the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, has a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppmFor which of the following reasons can natural pollutants play an important role in controlling air pollution?
Read the following passage and mark the letter A, B, C, or D to indicate the correct word for each of the blanks from 26 to 35. COULD COMPUTER GAMES BE GOOD FOR YOU AFTER ALLIn Britain, the average young person now spends more money on games each year than on going to the cinema or renting videos. But is this……..26……a bad thing? For years, newspaper reports have been ………27…..that children who spend too much time playing computer games become unsociable, bad- tempered, even violent as a……..28…… But new research,………29……out in both Europe and the USA, suggests that the opposite may be true.Indeed, playing some of the more complicated games may help people of all ages to improve certain skills. Researchers claim that this is because the games………30……the brain work harder in certain ways, like……..31……sounds and movements quickly and identifying what they are. The fact that people play the games repeatedly……..32……..that they get a lot of practice in these skills which are therefore likely to become highly developed.Social skills may benefit, too. Researchers in Chicago think that fans of first- person shooter games……33…… “Counterstrike” are better than non-players when it comes to building trust and co-operation, and that this……..34……them to make good friendships and become strong members of their communities. So rather than……..35…….up computer games, perhaps young people need to spend more time on them?Question 32
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 Royal ResidencesBuckingham Palace, Windsor Castle and the Palace of Holyroodhouse are the official (35)_______ of the Sovereign and, as such, serve as both home and office for The Queen, whose personal standard flies (36)________ Her Majesty is in residence.These buildings are used extensively for State ceremonies and Official entertaining and are opened to the (37)________ as much as these commitments allow.All are furnished with fine pictures and (38)________of art from the Royal Collection, which has been assembled over four centuries by successive sovereigns. Many of the State Apartments and rooms at the official residences have been in continuous use since their conception and many of the works of art are (39)________ in the rooms for which they were originally (40)________.The official residences are in (41)________ use and the style and manner in which they are (42)_______ to visitors reflects their working status. Rooms are kept as close to their normal (43)________ as possible. Inevitably, opening times are subject to change at short notice depending on circumstances.The Royal Collection, which is owned by The Queen as Sovereign in trust for her successors and the Nation, is administered by the Royal Collection Trust to which a proportion of admission and other income from visitors is directed.The remainder of this income funds the majority of the cost of restoring Windsor Castle which was badly (44)________ by fire in November 1992.Question 35
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 from 35 to 42. Life in the Universe Exobiology is the study of life that originates from outside of Earth. As yet, of course, no such a life forms have been found. Exobiologists, however, have done important work in the theoretical study of where life is most likely to evolve, and what those extraterrestrial life forms might be like.What sorts of planets are most likely to develop life? Most scientists likely to agree that a habitable planet must be terrestrial, or rock-based, with liquid surface water and biogeochemical cycles that somewhat resemble the continuous movement ands transformation of materials in the environment. These cycles include the circulation of elements and nutrients upon which life and the Earth’climate depend. Since (as far as we know) all life is carbon-based, a stable carbon cycle is especially important.The habitable zone is the region around a star in which planets can develop life. Assuming the need for liquid surface water, it follows that most stars around the size of our sun will be able to sustain habitable zones for billions of years. Stars that are larger than the sun are much hotter and burn out more quickly; life there may not have enough time to evolve. Stars that are smaller than the sun have different problems. First of all, planets is their habitable zones will be so close to the stars that they will be “tidally blocked”- that is one side of the planet will always face the star in perpetual daylight with the other side in perpetual night. Another possible obstacle to life on smaller stars is that they tend to vary in their luminosity, or brightness, due to flares and “star spots”. The variation can be large enough to have harmful effects on the ecosystem. Of course, not all stars of the right size will give rise to life; they also must have terrestrial planets with the right kind of orbits. Most solar systems have more than one planet, which influence each other’s orbits with their own gravity. Therefore, in order to have a stable system with no planets flying out into space, the width of a star’s habitable zone. This means that for life to evolve, the largest possible number of life-supporting planets in any star’s habitable zone is two. Finally, not all planets meeting the above conditions will necessarily develop life. One major threat is large, frequent asteroid and comet impacts, which will wipe out life each time it tries to evolve. The case of Earth teaches that having large gas gains, such as Saturn and Jupiter, in the outer part of the solar system can help keep a planet safe for life. Due to their strong gravitation, they tend to catch or deflect large objects before they can reach EarthThe word “which” in paragraph 3 refers to ______.