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2013职称英语理工类阅读理解原文答案译文之17A Sunshade for the PlanetEven with the best will1 in the world, reducing our carbon emissions is not going prevent global warming. It has become clear that even if we take the most strong measures to control emissions, the uncertainties in our climate models still leave open the possibility of extreme warming and rises in sea level. At the same time, resistance by governments and special interest groups makes it quite possible that the actions suggested by climate scientists might not be implemented soon enough.Fortunately, if the worst comes to the worse2, scientists still have a few tricks up their sleeves3. For the most part they have strongly resisted discussing these options for fear of inviting a sense of complacency that might thwart efforts to tackle the root of the problem. Until now, that is. A growing number of researchers are taking a fresh look at large-scale “geoengineering” projects that might b e used to counteract global warming. “I use the analogy of methadone4,” says Stephen Schneider, a climate researcher at Stanford University in California who was among the first to draw attention to global warming. “If you have a heroin addict, the correct treatment is hospitalization, and a long rehab. But if they absolutely refuse, methadone is better than heroin.Basically the idea is to apply “sunscreen” to the whole planet. One astronomer has come up with a radical plan to cool Earth: launch trillions of feather-light discs into space, where they would form a vast cloud that would block the sun’s rays.It’s controversial, but recent studies suggest there are ways to deflect just enough of the sunlight reaching the Earth’s surface tocounteract the warming produced by the greenhouse effect. Global climate models show that blocking just 1. 8 per cent of t he incident energy in the sun’s rays would cancel out the warming effects produced by a doubling of greenhouse gases in the atmosphere. That could be crucial, because even the most severe emissions-control measures being proposed would leave us with a doubling of carbon dioxide by the end of this century, and that would last for at least a century more.注释:1. the best will:昀好的愿望2. if the worst comes to the worst:如果昀昀糟糕的事情发生了。
2023年高考英语外刊时文精读精练 (14)Climate change and coral reefs气候变化与珊瑚礁主题语境：人与自然主题语境内容：自然生态【外刊原文】（斜体单词为超纲词汇，认识即可；下划线单词为课标词汇，需熟记。
）Human beings have been altering habitats—sometimes deliberately andsometimes accidentall y—at least since the end of the last Ice Age. Now, though, that change is happening on a grand scale. Global warming is a growing factor. Fortunately, the human wisdom that is destroying nature can also be brought to bear on trying to save it.Some interventions to save ecosystems are hard to imagine andsucceed. Consider a project to reintroducesomething similar to a mammoth(猛犸象)to Siberiaby gene-editing Asian elephants. Their feeding habits could restore the grassland habitat that was around before mammoths died out, increasing the sunlight reflected into space and helping keep carbon compounds(碳化合物)trapped in the soil. But other projects have a bigger chance of making an impact quickly. As we report, one example involves coral reefs.These are the rainforests of the ocean. They exist on vast scales: half a trillion corals line the Pacific from Indonesia to French Polynesia, roughly the same as the number of trees that fill the Amazon. They are equally important harbor of biodiversity. Rainforests cover18% of the land’s s urface and offer a home to more than half its vertebrate(脊椎动物的)species. Reefs occupy0.1% of the oceans and host a quarter of marine(海洋的)species.And corals are useful to people, too. Without the protection which reefs afford from crashing waves, low-lying islands such as the Maldives would have flooded long ago, and a billion people would lose food or income. One team of economists has estimated that coral’s global ecosystem services are worth up to $10trn a year. reefs are, however, under threat from rising sea temperatures. Heat causes the algae（海藻） with which corals co-exist, and on which they depend for food and colour, to generate toxins（毒素）that lead to those algae’s expulsion（排出）. This is known as “bleaching（白化）”, and can cause a coral’s death.As temperatures continue to rise, research groups around the world are coming up with plansof action. Their ideas include identifying naturally heat-resistant（耐热的）corals and moving themaround the world; crossbreeding（杂交）such corals to create strains that are yet-more heat-resistant; employing genetic editing to add heat resistance artificially; transplantingheat-resistant symbiotic（共生的）algae; and even repairing with the bacteria and other micro-organismswith which corals co-exist—to see if that will help.The assisted evolution of corals does not meet with universal enthusiasm. Without carbon reduction and decline in coral-killing pollution, even resistant corals will not survive the century. Some doubt whetherhumans will get its act together in time to make much difference. Few of these techniques are ready for action in the wild. Some, such as gene editing, are so controversial that it is doubtful they will be approved any time soon. scale is also an issue.But there are grounds for optimism. Carbon targets are being set and ocean pollution is being dealt with. Countries that share responsibilities for reefs are starting to act together. Scientific methods can also be found. Natural currents can be used to facilitate mass breeding. Sites of the greatest ecological and economical importance can be identified to maximise benefits.This mix of natural activity and human intervention could serve as a blueprint （蓝图）for other ecosystems. Those who think that all habitats should be kept original may not approve. But when entire ecosystems are facing destruction, the cost of doing nothing is too great to bear. For coral reefs, at least, if any are to survive at all, it will be those that humans have re-engineered to handle the future.【课标词汇精讲】1.alter （通常指轻微地）改动，修改；改变，（使）变化We've had to alter some of our plans.我们不得不对一些计划作出改动。
1The first snowHenry Wadsworth Longfellow The first snow came. How beautiful it was, falling so silently all day long, all night long, on the mountains, on the meadows, on the roofs of the living, on the graves of the dead!(1) All with(2) save(3) the river, that marked its course(4) by a winding black line across the landscape; and the leafless trees, that against the leaden sky(5) now revealed more fully the wonderful beauty and intricacies(6) of their branches. What silence, too, came with the snow, and what seclusion! Every sound was muffled(7), every noise changed to something soft and musical. No more tramping hoofs, no more rattling wheels! Only the chiming of sleigh-bells, beating as swift and merrily as the hearts of children(8).*注释(1) the living:活着的人；the dead:死去的人。
形容词（有时是分词）前面加上定冠词the 表示具有某一特性的一类人。
Ocean Plant Life in Decline海洋植物数量锐减1.Scientists have discovered plant life covering the surface of the world's oceans is disappearing at a dangerous rate. This plant life called phytoplankton is a vital resource that helps absorb the worst of the "greenhouse gases" involved in global warming. Satellites and ships at sea have confirmed the diminishing productivity of the microscopic plants, which oceanographers say is most striking in the waters of the North Pacific—ranging as far up as the high Arctic. "Whether the lost productivity of the phytoplankton is directly due to increased ocean temperatures that have been recorded for at least the past 20 years remains part of an extremely complex puzzle", says Watson W. Gregg, a NASA biologist at the Goddard Space Flight Center in the USA, but it surely offers a fresh clue to the controversy over climate change. According to Gregg, the greatest loss of phytoplankton has occurred where ocean temperatures have risen most significantly between the early 1980s and the late 1990s. In the North Atlantic summertime, sea surface temperatures rose about 1. 3 degrees Fahrenheit during that period, while in the North Pacific the ocean's surface temperatures rose about 0.07 of a degree.1、科学家们发现覆盖海洋表⾯的植物数量正在快速消失。
最牛英语口语培训模式：躺在家里练口语，全程外教一对一，三个月畅谈无阻！洛基英语，免费体验全部在线一对一课程：/ielts/xd.html（报名网址）Biology and financial instability生物学和金融界的不稳定性The molecules of mayhem混乱的分子The Hour Between Dog and Wolf: Risk-Taking, Gut Feelings and the Biology of Boom and Bust. By John Coates.狗和狼之间的那一刻：冒险、直觉和繁荣与萧条的生物学。
由约翰·科茨。
The financial crisis was caused by many things: greedy bankers, a glut of Chinese savings,shoddy regulation, an obsession with home ownership—take your pick. John Coates, once a trader on Wall Street and now a neuroscientist at Cambridge University, presents yet another culprit: biology, or, more precisely, the physiology of risk-taking. Financial traders, he says, are influenced by what is going on in their bodies as well as in the markets. Two steroid hormones—testosterone and cortisol—come out in force during the excesses of bull and bear markets.导致金融危机的因素有好几个：贪婪的银行家、中国的大笔储蓄、具误导性的监管制度、对拥屋的痴迷——任你挑选。
Journ al of Sha ngha i Univ er sity (En glish Edition ),2006,10(3):215-218Article ID :1007 6417(2006)03 0215 04Entanglement of atoms in Tavis Cummings modelDONG Chuan hua (董传华), ZHANG Ya li (张亚利)Depar tm ent of Phy sics ,College of Scien ces ,Shan ghai Un iver sity ,Shan gha i 200444,P .R .ChinaReceived Sep.24,2004; Revised Ja n.7,2005DO NG Chuan hua,Prof.,E mail:chdong@ma Abstract Entanglem ent is used to measure correlation between separated subsystems.von Neumann entropy is used to study evolu tions of entanglement of atoms in processes of interaction between atoms with the field prepared in coherent state.The effects of field intensity and detuning on entanglement a re investiga ted.It is shown that the entanglement exhibited osc illations in its evolutions,their amplitudes and mean values decrease with inc reasing field intensity.Oscillation frequenc ies increase with detuning,but the maximum values a re almost independent of detuning.Key words entanglem ent,entangled state,Jaynes Cummings model.PACS 2001 42.50. P1 IntroductionSuperposition principle is one of the fundamentals in quantum m echanics.A two level atom may be in the ground state |0 ,the excited state |1 o r the superpo sition states C 0|0 +C 1|1 .The coefficients C 0and C 1are complex probability amplitudes of |0 and |1 respectively.For a system consisting of two atoms,the state of total system may be in the direct p roduct states |0,1 or |1,0 .Acco rding to the superposition principle,the total system may also be in the superpo sition states 1 2(C 0|0,1 +C 1|1,0 ).This kind of superposition states of multi particle is called entan gled state.Recently,people have devoted much attention to the applications of entangled states in quantum information,such as quantum teleporting [1,2],quantumcopying and cloning [3],quantum cryptography andquantum secret sharing [4],and quantum computation [5].Various schemes of preparing entangledstates have been proposed [6].The concept of entan gling has been generalized to the states of multi parti cle system,i .e .,G reenberger Ho rne Zeilinger states.Various methods of preparing G H Z states have alsobeen proposed [7,8].Entangling can be realized with non local correlation and entanglement is defined to measure the degree ofnon local correlation.Some definitions of entanglement have been given [9,10].Zuo and Xia have studied the evolution properties of three body entanglement of two identical two level atoms in the presence of fieldin vacuum [11].Rendell and Rajagopal have studied the entanglement of initially entangled mixed state in damped Jaynes Cummings model and found the timeevolutions of the concurrence lower bound [12].In this paper,we will use the partial entropy to study evolu tions of entanglement for two atoms in the presence of the field in coherent state with Tavis Cummings model.Effects of light intensity and the detunning on evolutions of entanglement are investigated.2 Definition of entanglementConsidering a system consisting of two atoms A and B,its entanglement (partial entropy entanglement)E is defined with von Neumann entropy,i .e .E =S ( A )=S ( B ),(1)where A and B are reduced density operators of at oms A and B.von Neumann entropy is a generalization of Shannon entropy in classic system to quantum sys tem,which describes the quantum co rrelation betweenthe sub systems [13].von Neumann entropy is defined asS ( )=-tr( log 2 ).(2)With Schmidt decomposition,the density operato rs of atoms A and B can be written in the fo rmA=tr B( A B)=mj=12j|j A A!j|,B=tr A( A B)=mj=1 2j|j B B!j|,(3)where m∀min{dim H A,dim H B},H A and H B are the Hilbert subspaces of atoms A and B,respectively. It follows that A and B have m non zero eigenvalues j(j=1-m).The relation between E and j isE=-mj=1j log2 j.(4)For two atoms in the entangled states| AB=C1|1,1 +C2|1,0 +C3|0,1+C4|0,0 ,(5) the eigenvalues of A(or B)arej=121-(-1)j1-4|C1C4-C2C3|2,j=1or2.(6)The partial entropy entanglement can be calculated as follows.E=-( 1log2 1+ 2log2 2).(7) 3 Entanglement of two atoms in TavisCummings modelConsidering a system consisting of two level atoms A and B,the ground state and excited state are denot ed|0 and|1 respectively.The light field is initially prepared in the coherent state|! =nf n|n ,where f n=exp(- n 2)!n n!and n is mean photon num ber.Two atoms are in the entangled state|(0) ato m=1 2(|0,1 +|1,0 ).(8) This entangled state is one of Bell bases,which is maximally entangled state with entanglement E=1. The state evolves from the initial state to|(t) at time t>0|(t) =C1(t)|1,1;n-1 +C2(t)|1,0;n+C3(t)|0,1;n +C4(t)|0,0;n+1 ,(9) where the coefficients C j(t)(j=1-4)are to be de termined.In the interaction picture,the Hamiltonian of the system consisting of two atoms and a field in Tavis Cummings model is,H I=g(a+S-e i∀t+S+a e-i∀t),(10)where∀=#-#0,#0is the transiting frequency of at oms and#is the f requency of field,S+=S(A)++S(B)+, S-=S(A)-+S(B)-,and S(j)#(j=A or B)are the transit ing operato rs of atom A(or B).Substituting the inter action Hamiltonian Eq.(10)and the state vector Eq.(9)into the Schr dinger equation and solving it using a standard p rocedure with the initial condition Eq.(8), the coefficients C j(t),(j=1∃4)in Eq.(9)can be obtained as follows.C1(t)=-2n gm1∃1-∀[ei(∃1-∀)t-1]+m2∃2-∀[ei(∃2-∀)t-1]+m3∃3-∀[ei(∃3-∀)t-1],C2(t)=C3(t)=m1e i∃1t+m2e i∃2t+m3e i∃3t,C4(t)=-2n+1gm1∃1+∀[ei(∃1+∀)t-1]+m2∃2+∀[ei(∃2+∀)t-1]+m3∃3+∀[ei(∃3+∀)t-1],(11)wherem1=f n2∃2∃3+2(2n+1)g2(∃1-∃2)(∃1-∃3),m2=f n2∃1∃3+2(2n+1)g2(∃2-∃1)(∃2-∃3),m3=f n2∃1∃2+2(2n+1)g2(∃3-∃1)(∃3-∃2)(12)and∃1=2r1 3cos%,∃2=2r1 3cos(%+2& 3),∃3=2r1 3cos(%+4& 3),(13) r=[2(2n+1)g2+∀2]3 27,%=1 3arccos(-∀g2 r).(14) In the case of∀=0,C j(t)can be reduced toC1(t)=-i2nf n g sin(∋n t) ∋n,C2(t)=C3(t)=2-1 2f n cos(∋n t),C4(t)=-i2(n+1)f n g sin(∋n t) ∋n,(15) where Rabi frequency is2∋n and.(16)216J our nal of Shan gha i Univer sityThe reduced density operator of atom A can beobtainedA = n(|C 1|2+|C 2|2)|1 !1|+(|C 3|2+|C 4|2)|0 !0|+(C *2C 4+C *1C 3)|0 !1| +(C 2C *4+C 1C *3)|1 !0|,(17)its eigenvalues are =0.5(1#1-(),(18)where(=4[ n (|C 1|2+|C 2|2) n(|C 3|2+|C 4|2)- n(C 1C *3+C 2C *4)2].(19)Using Eq.(7),the evolutions of entanglement can be obtained,which are shown in Fig.1for the case of resonance.The atoms A and B are prepared initially in Bell base |1,0 +|0,1 ,so the initial entanglement is 1.In the processes of interaction between the atoms and the field,the state of the system consisting of at oms A and B will deviate from this Bell base.In case of resonance,the states will evolve to the state | (t ) at a time t >0,which can be rewritten as | (t ) =1 2 nf n {cos (∋n t )(|1,0;n +|0,1;n ) -i sin (∋n t )[1-1 (2n +1)|1,1n -1+1+1 (2n +1)|0,0;n +1 ]}=1 2 n f n {cos (∋n t )(|1,0;n +|0,1;n ) -i sin (∋n t )[(|1,1;n -1 +|0,0;n +1 )-1 (4n +2)(|1,1;n -1 -|0,0;n +1 )+%]}.(20)It can be seen from Eq.(20)that the other two Bellbases |1,1 #|0,0 appear in atom field interaction.These Bell bases evolve according to cosine and sine with frequency ∋n that is different for various pho ton numbers n .Superposing these Bell bases form the os cillations of entanglement in evolution. In a weaker field ( n <4),the valley values of oscil lations rise obviously with increasing field intensity so that the mean values of entanglements in the oscil lations increase (see Fig.1(a)-(c)).In a stronger field ( n >4),the mean values of entanglements de crease rapidly (see Fig.1(d)and (e)),and the am plitudes shrink sharply with enhancing the field.When n =15,entanglement is maintained roughly constant inevolution.Thus,enhancing the field makes the atomsdetangle.This can be explained by the fact that thequantum co rrelation is weakened due to enhancing the interaction of two atoms with the field respectively in a stronger field.Fig.1 Entanglement of two atoms in the case of resonanc e((a) n =0.2,(b) n =1.0,(c) n =4.0,(d) n =9.0,(e) n =15.0)Evolution of entanglement in off resonance are shown in Fig.2(for weaker field, n =0.2)and Fig.3(for stronger field, n =9).From these figures,it can be seen that oscillation frequencies increase and the amplitudes shrink with increasing detuning in a weaker field.Except these oscillations,there are slow varia tions with large amplitudes in evolution for a stronger field and large detuning.The minimum values rise in a weaker field (see Fig.2)and drop in a stronger field (see Fig.3)with increasing the detuning.The maxi mum values of entanglement in the evolution are inde pendent of detuning almost,while dependent only on the field intensity.In summary,in interactions between atoms and the field,entanglements of two atoms will oscillate due to the Rabi oscillations.The field intensity and the detun ing affect evolutions of atom entanglement.Entanglements of two atoms depend on the field in tensity.The mean entanglem ents increase slightly in a weak field and decrease obviously in a strong field217Vol.10 No.3 Jun.2006DONG C H,et al .: Entanglem ent of atom s in Tavis Cummings modelFig.2 Entanglement of two atoms in the case of off resonanc efor n =0.2((a)∀=0.5g ,(b)∀=2.0g ,(c)∀=4.0g ,(d)∀=10.0g ,(e)∀=20.5g)Fig.3 Entanglement of two atoms in the case of off resonanc efor n =9.0((a)∀=0,(b)∀=0.5g ,(c )∀=1.0g ,(d)∀=4.0g ,(e)∀=10g )with increasing field intensity.It follows that a strong field makes the atoms detangle.The amplitudes of oscillations of entanglements shrink sharply with in creasing field intensity.The maximum values of entan glement are independent of detuning but dependent on the field intensity.The oscillation frequencies increase and the amplitudes shrink in a weak field with the increasing detuning.References[1] Bennett C H,Wiesner S munication v ia one andtwo particle operators on Einstein Podolsky Rosen states [J].Phys .Rev .Lett .,1992,69(20):2881-2884.[2] Bennett C H,Brassard G,Cr peau C,et al .Teleportingan unknown quantum state via dual classical and Ein stein Podolsky Rosen c hannels [J].Phy s .Rev .Lett .,1993,70(13):1895-1898.[3] Buzek V,H illery M.Quantum copying:Beyond the nocloning theorem[J].Phys .Rev .,1996,A54(3):1844-1852.[4] Hillery M,Buzek V,Berthiaume A.Quantum secret sharing[J].Phys .Rev .,1999,A59(3):1829-1834.[5] Anders S rensen,Klaus M lme r.Entanglement and quantum computation with ions in the therm al motion [J ].Phys .Rev .,2000,A 62(2):022311 1-022311 11.[6] Cirace J I,Zoller P.Preparation of macroscopic superposition in many atom systems [J ].Phy s .Rev .,1994,A50(4):R2799-R2802.[7] Yao C M,Guo G C.Generation of spin type G HZ statesof the cavity field in squeezed coherent states[J].Acta Phy sica Sinica ,2001,50(1):59-62(in Chinese).[8] Liu X,Li H C.Prepa ration of multi atom GHZ states v iathe Raman interaction of V type three level atoms and one cavity field[J].Acta Phy sica Sin ica ,2001,50(9):1689-1692(in Chinese).[9] Vedral V,Plenio M B,Rippin M A,et al .Quantifyingentanglement[J].Phys .Rev .Lett .,1997,78(12):2275-2279.[10] Vedral V,Plenio M B.Entanglement measures and purification procedures[J].Phy s .Rev .,1998,A57:1619-1633.[11] Zhou Z C,Xia Y J.The evolution property of three bodyentanglement measure in Tavis Cumm ings model [J ].Acta Physica Sinica ,2003,52(11):2687-2693(in Chinese).[12] Rendell R W,Rajagopal A K.Revivals and entanglementfrom initially entangled mixed sta tes of a damped Jaynes Cumm ings model [J].Phys .Rev .,2003,A67(6):062110 1-062110 11.[13] von Neumann.Mathem atical F oundat ion s of Qua ntumMechan ics [M].Princeton University Press,Princeton,NJ,1955.(Editor YAO Yu e yuan )218J our nal of Shan gha i Univer sity。
The Formation of Coral Reefs and Atolls Coral reefs and atolls are some of the most fascinating and diverse ecosystems on the planet. They are formed from the accumulation of calcium carbonate exoskeletons of coral polyps, which are tiny, invertebrate animals that live in colonies. These structures provide a habitat for a wide variety of marine life, including fish, invertebrates, and algae. The formation of coral reefs and atolls is a complex process that involves geological, biological, and environmental factors.One of the key factors in the formation of coral reefs and atolls is the presence of suitable substrate for coral growth. Coral polyps require a hard surface on which to attach and grow, and they typically thrive in warm, shallow, clear waters. As the polyps grow and reproduce, they form colonies that eventually build up into large, solid structures. Over time, the accumulation of coral skeletons creates the framework for a reef or atoll.The geological processes that contribute to the formation of coral reefs and atolls are also important to consider. Reefs often form along the edges of continents or around volcanic islands, where the ocean floor is relatively shallow. As the Earth's tectonic plates shift and move, these areas can experience changes in sea level and land elevation, which can impact the growth and development of coral reefs. Additionally, the presence of ocean currents and wave action can influence the shape and structure of reefs, as well as the distribution of coral species.In addition to geological factors, biological processes play a crucial role in the formation of coral reefs and atolls. Coral polyps rely on a symbiotic relationship with photosynthetic algae called zooxanthellae, which live within their tissues and provide them with essential nutrients. This relationship allows corals to thrive in nutrient-poor waters, but it also makes them sensitive to environmental stressors such as changes in temperature and water quality. When corals are stressed, they can expel their zooxanthellae, a process known as coral bleaching, which can have devastating effects on reef ecosystems.The environmental conditions in which coral reefs and atolls form and grow are also significant. These ecosystems are typically found in tropical and subtropical regions, wherethe water is warm and clear. The availability of sunlight is crucial for the photosynthetic processes of both corals and their symbiotic algae, so reefs are most commonly found in shallow waters where light can penetrate. Additionally, the stability of water temperature and chemistry is important for the health and growth of coral reefs, as they are sensitive to changes in conditions such as ocean acidification and pollution.Human activities also play a role in the formation and degradation of coral reefs and atolls. Overfishing, destructive fishing practices, coastal development, and pollution can all have negative impacts on reef ecosystems. Additionally, climate change is a major threat to coral reefs, as rising sea temperatures and ocean acidification are causing widespread coral bleaching and mortality. Conservation efforts, such as marine protected areas and sustainable fishing practices, are essential for the preservation of these valuable and vulnerable ecosystems.In conclusion, the formation of coral reefs and atolls is a complex and dynamic process that involves a combination of geological, biological, and environmental factors. These ecosystems are not only incredibly diverse and beautiful, but they also provide important ecological and economic benefits. Understanding the processes that shape coral reefs and atolls is crucial for their conservation and management, especially in the face of growing threats from human activities and climate change. As stewards of the natural world, it is our responsibility to protect and preserve these irreplaceable ecosystems for future generations.。
第八章人口问题The world can be divided into two segments based on the state of economic development of the countries.根据国家的经济发展状况，世界可以分成两个部分。
Collectively, the more-developed countries of the world have relatively stable populations and are expected to grow by about 4 percent by 2050. The less-developed regions of the world，however, have high population growth rates and are expected to grow by about 55 percent by 2050.总体而言，世界上发达国家的人口数量比较稳定，预计到2050年增长4%。
但是，世界上欠发达国家的人口增长率非常高，预计到2050年增长55%。
Human population growth is tied to economic development and is a contributing factor to nearly all environmental problems.人口增长与经济发展紧密相连，在几乎所有的环境问题中，人口增长都是一个影响因子。
It is clear that as the population continues to increase, it will become more difficult to limit the environmental degradation that accompanies it.人们非常清楚，随着人口继续增长，限制随之而来的环境恶化将变得更加困难。
高二全球气候与环境保护英语阅读理解25题1<背景文章>Global warming has become one of the most pressing issues in the world today. There are several main reasons for this phenomenon. First of all, the excessive emission of greenhouse gases, such as carbon dioxide, is a major culprit. The burning of fossil fuels like coal, oil, and gas in industries, transportation, and power generation releases a large amount of carbon dioxide into the atmosphere. Deforestation also plays a significant role. Trees act as natural carbon sinks, absorbing carbon dioxide from the air. However, large - scale deforestation for agriculture, logging, and urban expansion has reduced the number of trees available to absorb carbon dioxide.The impacts of global warming are far - reaching. Sea - level rise is a very obvious consequence. As the temperature rises, glaciers and ice sheets melt, adding more water to the oceans. This not only threatens low - lying islands and coastal areas but also disrupts the habitats of many marine organisms. Extreme weather events are becoming more frequent and intense. Heatwaves, droughts, floods, and stronger hurricanes are occurring more often, causing great damage to human lives and property.Regarding solutions, there are multiple approaches. One importantstep is to transition to clean energy sources. Renewable energy such as solar, wind, hydro, and geothermal power can significantly reduce the reliance on fossil fuels. Energy conservation is also crucial. Improving energy efficiency in buildings, industries, and transportation can cut down energy consumption. For example, using energy - efficient appliances and promoting public transportation.Different countries have different attitudes towards dealing with global warming. Developed countries generally have more advanced technologies and greater financial resources. Some of them are taking positive actions to reduce emissions and promote international cooperation. For instance, European countries have been actively promoting the use of clean energy and setting strict emission reduction targets. However, developing countries may face more challenges. They need to balance economic development with environmental protection. Some developing countries are also making efforts. For example, China is investing heavily in renewable energy development and has made remarkable achievements in reducing emissions in recent years.1. What is the major cause of global warming according to the passage?A. The use of renewable energy.B. The excessive emission of greenhouse gases.C. The increase of sea - level.D. The protection of forests.答案：B。
In order to solve a burglary that has taken place at the Marshalls' house, Detective Johnson has been instructed to search exactly seven locations—the foyer, the kitchen, the living room, the guest room, the hallway, the music room, and the nursery. The foyer, kitchen, and living room are located downstairs, whereas the guest room, hallway, music room, and nursery are located upstairs. During the first visit to search for evidence, Detective Johnson hastime to search exactly three locations. This search must be conducted accordingto the following conditions:The three locations searched must be neither all upstairs nor all downstairs.If the hallway is searched, then the foyer must also be searched.If the music room is not searched, then the guest room cannot be searched.The kitchen and the living room cannot both be searched.The three locations searched must include the living room or the nursery, or both. Which of the following is a selection of locations that conforms to theconditions for Detective Johnson's first visit?Foyer, guest room, hallwayFoyer, hallway, living roomFoyer, kitchen, living roomGuest room, hallway, kitchenGuest room, music room, nursery————————————————————————答案：(B)During the first visit, if the kitchen is searched, which of the followingmust also be searched?The foyerThe guest roomThe hallwayThe music roomThe nursery————————————————————————答案：(E)During the first visit, if the music room is searched, which of the followingis a pair of locations that can both also be searched?The foyer and the hallwayThe guest room and the kitchenThe hallway and the living roomThe kitchen and the living roomThe kitchen and the nursery————————————————————————答案：(E)During the first visit, if the guest room is searched, which of the followingmust also be searched?The foyerThe hallwayThe kitchenThe living roomThe nursery————————————————————————答案：(D)During the first visit, if the kitchen is the only downstairs locationsearched, which of the following must also be searched?The music room and the nurseryThe hallway and the nurseryThe hallway and the music roomThe guest room and the nurseryThe guest room and the music room————————————————————————答案：(A)During the first visit, if the living room is not searched, which of thefollowing is a pair of locations that can both be searched?The foyer and the guest roomThe hallway and the kitchenThe foyer and the music roomThe hallway and the music roomThe guest room and the kitchen————————————————————————答案：(C)The presence of microorganisms that produce a toxin causes seawater to turn brownish red, a phenomenon known as a red tide. Sea otters do not feed in areas where clams, their main source of food, have become contaminated with this toxin. According to a proposed explanation of the otters' behavior, the otters sample the clams in a potential feeding area and can taste any toxin in them.Which of the following, if true, would most strongly indicate that thehypothesis described in the last sentence of the passage is not correct?In some of the areas where red tides occur, neither clams nor sea otters areindigenous species.The presence of sea otters in a given area has a significant effect on whichother marine organisms are to be found in that area.When seawater in an area unaffected by red tide is artificially dyed brownishred, sea otters do not feed on the clams in that area.If the clams in a given area are contaminated with toxins, sea otters move toother areas in search of food.Although very small amounts of the toxin produced during a red tide are notharmful, large doses can be fatal to animals the size of sea otters.————————————————————————答案：(C)问题：下面哪一个，if true，最强烈地指出上文最后一句话所描述的假设是不正确的读题：产生一种毒质的微生物的存在引起海水变为褐红色，我们称之为红潮的现象。
