Some schools have started distributing study materials to students electronically via computers, with the belief that this will increase students' enthusiasm and efficiency in learning. An education expert concludes that teachers will be replaced by computers in the future.
Which of the following, if true, most seriously weakens the education expert's conclusion?
(A) Despite the vast amount of information available in libraries, the number of teaching positions has remained steady over time.
(B) Computers can provide students with access to a wide range of knowledge, reducing the need for teachers.
(C) The rapid development of computer technology allows students to obtain more up-to-date information from computers than from teachers.
(D) Many students find it more engaging to learn from interactive computer programs than from traditional classroom lectures.
(E) Some schools have begun to incorporate computer-based learning materials into their curricula to supplement teacher instruction.
Linguists have observed that two groups of people express the concepts of time "ahead" and "behind" in opposite ways. Lymin English speakers use "behind" to represent the past and "ahead" for the future, while Ameniya speakers do the reverse, using "ahead" for the past and "behind" for the future. Additionally, research has found that when referring to time, general English speakers tend to sway their hands backward when referring to the past and forward when mentioning the future. Conversely, Ameniya speakers gesture forward for the past and backward for the future.
The findings from the passage, if accurate, most strongly support which of the following conclusions?
(A) The use of "ahead" and "behind" to describe time is an innate human characteristic independent of language and culture.
(B) Gestures accompanying speech are learned behaviors that are not influenced by the speaker's native language.
(C) The concepts of past and future are fundamentally different in Lymin English and Ameniya languages.
(D) People's physical feedback when speaking about time tends to align with their language's visualization of temporal concepts.
(E) Linguistic and cultural differences between groups have no impact on how individuals conceptualize and express time.
AD
2.RC
Squeaking sand produces sounds with very high frequencies—between 500 and 2,500 hertz, lasting less than a quarter of a second. The peals are musically pure, often containing four or five harmonic overtones. Booming sand makes louder, low-frequency sounds of 50 to 300 hertz, which may last as long as 15 minutes in larger dunes (although typically they last for seconds or less). In addition, they are rather noisy, containing a multitude of nearby frequencies. Booms have never been observed to contain more than one harmonic of the fundamental tone.
These dramatic differences once led to a consensus that although both types of sand produce acoustic emissions, the ways in which they do so must be substantially different. In the late 1970s, however, Peter K. Haff, then at the California Institute of Technology, produced squeaks in booming sand, suggesting a closer connection between the two.
Both kinds of sand must be displaced to make sounds. Walking on some sand, for example, forces the sand underfoot to move down and out, producing squeaks. In the case of booming sand, displacement occurs during avalanches.
It is within the avalanche that sound begins and where the answers must be hiding. Before an avalanche can occur, winds must build a dune up to a certain angle, usually about 35 degrees for dry desert sand. Once the angle is achieved, the sand on the leeward side of the dune begins to slump. Intact layers of sand slip over the layers below, like a sheared deck of cards. At the same time, the individual grains in the upper layers tumble over the grains underneath, momentarily falling into the spaces between them and bouncing out again to continue their downward journey. Their concerted up-and-down motion is believed to be the secret source of sound. Fully developed avalanches, in which sliding plates of sand remain intact for most of their motion, have the greatest acoustic output. In some places, where large amounts of sand are involved, booming can be heard up to 10 kilometers away.
The mysteries of the vibrations are many. To begin with, the multiple frequencies of booming sand are not well understood. In the 1970s David R. Criswell and his collaborators at the University of Houston found that each frequency seems to exhibit its own rise-and-fall time, independent of the others. Taken together, these frequencies can cover a fairly broad range, the width of which is determined by various factors. For example, Sand Mountain booms at roughly 50 to 80 hertz; sands at Korizo, Libya, drone at between 50 and 100 hertz; and in the Kalahari Desert of South Africa, the frequencies range from 130 to 300 hertz. Such output—presumably caused by multiple modes of vibration within the shearing plates—is often unmusical and jarring.
Because it is caused by large volumes of shearing sand, the roaring is also loud. In fact, sounds made by booming sand can be nearly deafening, and the vibrations causing them can be so intense that standing in their midst is nearly impossible.
A good place to start in exploring the vibrational properties of sand is with the grains themselves. The mean diameter of most sand grains, whether acoustically active or not, is about 300 microns. Usually the grains in a booming dune are very similar in size, especially near the leeward crest, where the sound most often originates; such uniformity allows for more efficient shearing. Otherwise, the smaller grains impede the smooth motion of the larger ones.
Similar sizes do not alone allow sand to boom. On the contrary, the booming sands of Korizo and Gelf Kebib, also in Libya, feature an uncharacteristically broad range of particle sizes. Moreover, silent dune sand often contains grains somewhat similar to nearby booming sand.
Grains of booming sand also tend to have uncommonly smooth surfaces, with protrusions on the scale of mere microns. Booming dunes are often found at the downwind end of large sand sources; having bounced and rolled across the desert for long distances, the sand grains in these dunes are usually highly polished. Over time a grain can also be polished by repeated shifts within a moving dune. And squeaking sand as well tends to be exceptionally smooth.
Close inspection of Sand Mountain and Kalahari booming sand, however, reveals that not all grains are highly spherical or rounded. And in 1936 A. D. Lewis in Pretoria, South Africa, even claimed to have produced booming in the cubed grains of ordinary table salt. Conversely, spherical glass beads cannot be made to boom. These findings show that although smoothness and roundness are essential to producing sound, so is some degree of roughness.
Another important factor is humidity, because moisture can modify the friction between the grains or cause sand to clump together, thus precluding shearing. Sounds occur in those parts of the dune that dry the fastest. Precipitation may be rare in the desert, but dunes retain water with remarkable efficiency. Sand near the surface dries quickly, however, and sand around a dune’s crest tends to dry the fastest.
Near the leeward crest, the combination of smooth, well-sorted grains and lack of moisture leads to conditions more likely to produce sounds during shearing. And because wind usually deposits more sand closer to the top of the lee face, sand accumulates there faster than in lower regions, thereby slowly increasing the dune’s incline to where avalanches occur.
Typically, large platelike slabs of sand break off near the crest. In booming sand, these plates tend not to slow into loose flows as they encounter gentler slopes. Instead their upper parts collapse or telescope violently into the lower parts. The plates’ eventual breakup is unusually turbulent.
Learning more about sound-producing sand has not been easy. Research has been hindered by the rarity of the phenomenon—especially booming sand —and the difficulty in reproducing sounds in laboratories. In addition, for years researchers did not clearly differentiate between booming and squeaking sands, making the early literature on the topic less than reliable.
Question 1: The author's discussion of the findings of David R. Criswell and his collaborators at the University of Houston primarily serves to:
(A) Provide evidence that contradicts the main thesis of the passage
(B) Introduce a new theory that explains the multiple frequencies of booming sand
(C) Highlight the complexity and lack of understanding surrounding the vibrations in booming sand
(D) Demonstrate the superiority of their research methods compared to those of other scientists
(E) Suggest that the rise-and-fall times of frequencies are the key to understanding sound production in sand
Question 2: The passage suggests that the relationship between grain size and sound production in sand is:
(A) Straightforward, with smaller grains always producing higher frequencies
(B) Inverse, with larger grains producing louder sounds
(C) Nonexistent, as grain size has no bearing on sound production
(D) Complex, with both uniformity and some variation in size being important factors
(E) Dependent on the location of the sand dune and the prevailing wind patterns
Question 3: The author's mention of A. D. Lewis's claim to have produced booming in the cubed grains of ordinary table salt serves to:
(A) Provide support for the idea that smoothness and roundness are essential for sound production
(B) Suggest that the shape of sand grains is more important than their size in determining acoustic properties
(C) Introduce a new hypothesis about the role of grain shape in sound production
(D) Demonstrate that roughness, in addition to smoothness and roundness, plays a role in sound production
(E) Challenge the notion that booming sand is a rare phenomenon
Question 4: Based on the information in the passage, which of the following can be inferred about the relationship between moisture and sound production in sand?
(A) Moisture has no effect on the acoustic properties of sand
(B) The presence of moisture always enhances the ability of sand to produce sounds
(C) Moisture content must be within a specific range for sand to produce sounds
(D) Sound production is more likely to occur in areas of the dune that dry quickly
(E) Booming and squeaking sands require different levels of moisture to produce sounds
Question 5: The passage suggests that the telescoping of sand plates during an avalanche is:
(A) A rare occurrence that has little impact on sound production
(B) The primary reason why booming sand produces lower frequencies than squeaking sand
(C) A phenomenon that occurs only in the largest sand dunes
(D) A characteristic of booming sand avalanches that contributes to their turbulent nature
(E) The result of the sand grains being highly spherical and rounded
Question 6: The author's attitude towards the current state of research on sound-producing sand can best be described as:
(A) Optimistic about the potential for future breakthroughs
(B) Disappointed by the lack of progress in recent years
(C) Excited by the discovery of new types of sound-producing sand
(D) Cautiously hopeful despite acknowledging significant challenges
(E) Dismissive of the contributions made by early researchers
Question 7: According to the passage, which of the following factors contributes to the efficiency of shearing in booming sand?
(A) The presence of moisture between the sand grains
(B) A wide range of particle sizes within the dune
(C) Highly polished surfaces on the sand grains
(D) The steepness of the leeward side of the dune
(E) Strong winds blowing across the surface of the dune
Question 8: The passage is primarily concerned with:
(A) Comparing and contrasting the acoustic properties of booming and squeaking sands
(B) Arguing for the superiority of one theory of sound production in sand over others
(C) Describing the current understanding of sound production in sand and the challenges faced by researchers
(D) Providing a comprehensive history of research on sound-producing sand
(E) Advocating for increased funding and resources for the study of sound-producing sand
Answers:
C
D
D
D
D
D
C
C
3.DI
The Pacific Island nations, scattered across the vast expanse of the Pacific Ocean, have long relied on the bounty of the sea for their sustenance, livelihoods, and economic development. The region's exclusive economic zones (EEZs) cover approximately 30 million square kilometers, accounting for roughly 28% of the world's EEZs. These waters are home to some of the most productive and diverse marine ecosystems on the planet, supporting a wide range of fish species, including tuna, billfish, and reef fish.
However, the sustainability of these vital marine resources has come under increasing threat in recent decades, due to factors such as overfishing, illegal, unreported, and unregulated (IUU) fishing, climate change, and pollution. The Western and Central Pacific Ocean, which encompasses the majority of the Pacific Island nations' EEZs, is the world's largest tuna fishery, accounting for over 50% of the global tuna catch. The region's tuna fisheries, particularly those targeting skipjack, yellowfin, and bigeye tuna, are of critical importance to the economies of many Pacific Island nations, generating an estimated $2.5 billion in revenue annually and providing employment for over 30,000 people.
Despite the economic significance of the tuna fisheries, the Pacific Island nations have historically struggled to maximize the benefits from these resources, due to a combination of factors, including limited domestic fishing capacity, inadequate infrastructure, and unfavorable access agreements with distant water fishing nations (DWFNs). In recent years, however, the Pacific Island nations have taken significant steps to assert greater control over their fisheries resources and to ensure their sustainable management for future generations.
One of the key initiatives in this regard has been the establishment of the Western and Central Pacific Fisheries Commission (WCPFC) in 2004, a regional fisheries management organization (RFMO) that brings together the Pacific Island nations, DWFNs, and other stakeholders to promote the conservation and sustainable use of the region's tuna stocks. The WCPFC has adopted a range of conservation and management measures, such as catch limits, vessel monitoring systems, and observer programs, to ensure the long-term sustainability of the tuna fisheries.
In addition to regional cooperation through the WCPFC, the Pacific Island nations have also taken steps to strengthen their domestic fisheries governance frameworks. Many countries have developed national tuna management plans, which set out strategies for the sustainable development of their tuna industries, including measures to promote local participation, value addition, and employment. Some countries, such as Papua New Guinea and Solomon Islands, have also established onshore processing facilities to capture a greater share of the value from their tuna resources.
Another key challenge facing the Pacific Island nations is the need to combat IUU fishing, which is estimated to cost the region up to $600 million annually in lost revenue. IUU fishing not only undermines the sustainability of the region's fisheries but also deprives Pacific Island nations of much-needed income and employment opportunities. To address this issue, the Pacific Island nations have implemented various measures, such as the use of satellite-based vessel monitoring systems, the deployment of trained observers on fishing vessels, and the strengthening of regional and international cooperation to detect and deter IUU fishing activities.
Climate change poses another significant threat to the Pacific Island nations' fisheries resources, with rising sea temperatures, ocean acidification, and changing weather patterns all expected to have profound impacts on marine ecosystems and fish stocks. The Pacific Island nations are among the most vulnerable to the impacts of climate change, despite contributing minimally to global greenhouse gas emissions. In response, the Pacific Island nations have been at the forefront of global efforts to address climate change, advocating for ambitious emissions reductions targets and adaptation measures to build resilience in their communities and economies.
Despite the challenges faced by the Pacific Island nations in managing their fisheries resources sustainably, there have been some notable successes in recent years. For example, the implementation of the Vessel Day Scheme (VDS) by the Parties to the Nauru Agreement (PNA), a subregional grouping of eight Pacific Island nations, has significantly increased the economic returns from the region's tuna fisheries. Under the VDS, fishing access is allocated through a system of tradable fishing days, which has helped to create competition among DWFNs and to drive up the price of access fees. As a result, the PNA countries have seen a more than threefold increase in revenue from their tuna fisheries over the past decade, from $60 million in 2010 to over $500 million in 2020.
Looking to the future, the Pacific Island nations will need to continue to work together to address the complex challenges facing their fisheries resources, while also seeking to maximize the economic and social benefits from these resources for their populations. This will require sustained investments in fisheries management, infrastructure, and capacity building, as well as continued engagement with regional and international partners to address cross-cutting issues such as climate change, IUU fishing, and sustainable development.
One promising area for future growth and development is the promotion of sustainable coastal fisheries and aquaculture, which have the potential to provide alternative livelihoods and food security for coastal communities, while also relieving pressure on offshore tuna stocks. Many Pacific Island nations have rich traditions of coastal fishing and aquaculture, and there is growing interest in developing these sectors in a sustainable and culturally appropriate manner.
Another key priority for the Pacific Island nations will be to continue to assert their sovereign rights over their fisheries resources, and to ensure that they are able to derive fair and equitable benefits from these resources. This may involve negotiating more favorable access agreements with DWFNs, developing domestic fishing industries and value-adding activities, and exploring innovative financing mechanisms such as blue bonds and impact investment to support sustainable fisheries development.
Ultimately, the sustainable management of the Pacific Island nations' fisheries resources will require a long-term, holistic approach that balances the needs of current and future generations, while also recognizing the cultural, social, and economic significance of these resources for the region's peoples. By working together and embracing innovative solutions, the Pacific Island nations have the potential to build a thriving and sustainable blue economy that benefits all.
Questions:
According to the passage, the Pacific Island nations' exclusive economic zones (EEZs) cover approximately what percentage of the world's EEZs?
(A) 10%
(B) 20%
(C) 28%
(D) 35%
(E) 50%
The Western and Central Pacific Ocean, which encompasses the majority of the Pacific Island nations' EEZs, accounts for what percentage of the global tuna catch?
(A) 20%
(B) 35%
(C) 50%
(D) 65%
(E) 80%
The passage suggests that the Pacific Island nations have historically struggled to maximize the benefits from their fisheries resources due to all of the following reasons EXCEPT:
(A) Limited domestic fishing capacity
(B) Inadequate infrastructure
(C) Unfavorable access agreements with distant water fishing nations (DWFNs)
(D) Lack of regional cooperation
(E) Climate change
The Western and Central Pacific Fisheries Commission (WCPFC) was established in which year?
(A) 2000
(B) 2004
(C) 2008
(D) 2012
(E) 2016
According to the passage, illegal, unreported, and unregulated (IUU) fishing is estimated to cost the Pacific Island nations up to how much annually in lost revenue?
(A) $100 million
(B) $300 million
(C) $600 million
(D) $900 million
(E) $1.2 billion
The passage indicates that the Pacific Island nations have taken all of the following steps to strengthen their domestic fisheries governance frameworks EXCEPT:
(A) Developing national tuna management plans
(B) Promoting local participation in the tuna industry
(C) Establishing onshore processing facilities
(D) Implementing vessel day schemes
(E) Investing in fisheries research and development
The Parties to the Nauru Agreement (PNA), a subregional grouping of eight Pacific Island nations, has seen a significant increase in revenue from their tuna fisheries over the past decade through the implementation of which scheme?
(A) Vessel Day Scheme (VDS)
(B) Catch Documentation Scheme (CDS)
(C) Regional Observer Program (ROP)
(D) Illegal, Unreported, and Unregulated Fishing Scheme (IUUFS)
(E) Sustainable Coastal Fisheries Scheme (SCFS)
The passage suggests that one promising area for future growth and development in the Pacific Island nations is:
(A) The expansion of distant water fishing fleets
(B) The promotion of sustainable coastal fisheries and aquaculture
(C) The development of deep-sea mining industries
(D) The establishment of large-scale fish farming operations
(E) The exploitation of previously untapped fisheries resources
The author's primary purpose in writing this passage is to:
(A) Advocate for increased foreign investment in the Pacific Island nations' fisheries sector
(B) Analyze the economic and social impacts of climate change on the Pacific Island nations
(C) Discuss the challenges and opportunities facing the Pacific Island nations in managing their fisheries resources sustainably
(D) Compare the fisheries management approaches of different Pacific Island nations
(E) Critique the role of distant water fishing nations in the Pacific Island nations' fisheries sector
The tone of the passage can best be described as:
(A) Optimistic and celebratory
(B) Pessimistic and critical
(C) Neutral and unbiased
(D) Cautiously optimistic
(E) Deeply skeptical
C: teachers will be replaced by computers in the future.
削弱方向：teachers不会被computers替代
A：虽然现在libraries也提供了很多信息，老师的数量还是稳定
这里computers和libraries都是提供学生的学习资料，所以可以类比
CR-2
C：用ahead表述past的人，在描述past的时候手是往前摆的；behind同理
推测:
表述概念(language's visualization of temporal concepts.)=手摆的方向（physical feedback）
D
[/md]作者: Ciel.W 时间: 2024-10-12 20:57
[md]CR：
1. 学校开始用电子资料→Teacher被computer replaced，问削弱，A选项用现状说明没有被替代，但是个人对E有疑惑，觉得E在说电子资料只是补充作用，（可能是脑补了补充作用不等于替代？）
2. 两种人对于两种时间概念的表达相反，同时他们表达两种概念的手势也不一样。选项D：People's physical feedback（对应手势） when speaking about time tends to align with their language's visualization of temporal concepts（对应概念表达）.