Questões do ENEM: nível difícil

Use os filtros para chegar às questões que interessam. Cada resultado abre em uma página própria com enunciado, alternativas e gabarito.

Resultados

9.777 questões encontradas. Mostrando a página 42 de 489.

  • 7E5C6294-92

    Inglês

    Análise sintática | Syntax Parsing
    UECE · 2020DifícilEntre para guardar nos favoritos
    Americans May Add Five Times More Plastic to the Oceans Than Thought

    The United States is using more
    plastic than ever, and waste exported for
    recycling is often mishandled, according
    to a new study.
    The United States contribution
    to coastal plastic pollution worldwide is
    significantly larger than previously
    thought, possibly by as much as five
    times, according to a study published
    Friday. The research, published in Science
    Advances, is the sequel to a 2015 paper
    by the same authors. Two factors
    contributed to the sharp increase:
    Americans are using more plastic than
    ever and the current study included
    pollution generated by United States
    exports of plastic waste, while the earlier
    one did not.
    The United States, which does
    not have sufficient infrastructure to
    handle its recycling demands at home,
    exports about half of its recyclable waste.
    Of the total exported, about 88 percent
    ends up in countries considered to have
    inadequate waste management.
    “When you consider how much
    of our plastic waste isn’t actually
    recyclable because it is low-value,
    contaminated or difficult to process, it’s
    not surprising that a lot of it ends up
    polluting the environment,” said the
    study’s lead author, Kara Lavender Law,
    research professor of oceanography at
    Sea Education Association, in a
    statement.
    The study estimates that in
    2016, the United States contributed
    between 1.1 and 2.2 million metric tons of
    plastic waste to the oceans through a
    combination of littering, dumping and 
    mismanaged exports. At a minimum,
    that’s almost double the total estimated
    waste in the team’s previous study. At the
    high end, it would be a fivefold increase
    over the earlier estimate.
    Nicholas Mallos, a senior
    director at the Ocean Conservancy and an
    author of the study, said the upper
    estimate would be equal to a pile of
    plastic covering the area of the White
    House Lawn and reaching as high as the
    Empire State Building.
    The ranges are wide partly
    because “there’s no real standard for
    being able to provide good quality data on
    collection and disposal of waste in
    general,” said Ted Siegler, a resource
    economist at DSM Environmental
    Solutions, a consulting firm, and an
    author of the study. Mr. Siegler said the
    researchers had evaluated waste-disposal
    practices in countries around the world
    and used their “best professional
    judgment” to determine the lowest and
    highest amounts of plastic waste likely to
    escape into the environment. They settled
    on a range of 25 percent to 75 percent.
    Tony Walker, an associate
    professor at the Dalhousie University
    School for Resource and Environmental
    Studies in Halifax, Nova Scotia, said that
    analyzing waste data can amount to a
    “data minefield” because there are no
    data standards across municipalities.
    Moreover, once plastic waste is shipped
    overseas, he said, data is often not
    recorded at all.
    Nonetheless, Dr. Walker, who
    was not involved in the study, said it
    could offer a more accurate accounting of
    plastic pollution than the previous study,
    which likely underestimated the United
    States’ contribution. “They’ve put their
    best estimate, as accurate as they can be
    with this data,” he said, and used ranges,
    which underscores that the figures are
    estimates.
    Of the plastics that go into the
    United States recycling system, about 9
    percent of the country’s total plastic
    waste, there is no guarantee that they’ll
    be remade into new consumer goods. New
    plastic is so inexpensive to manufacture
    that only certain expensive, high-grade
    plastics are profitable to recycle within the
    United States, which is why roughly half
    of the country’s plastic waste was shipped
    abroad in 2016, the most recent year for
    which data is available.
    Since 2016, however, the
    recycling landscape has changed. China
    and many countries in Southeast Asia
    have stopped accepting plastic waste
    imports. And lower oil prices have further
    reduced the market for recycled plastic.
    “What the new study really underscores is
    we have to get a handle on source
    reduction at home,” Mr. Mallos said. “That
    starts with eliminating unnecessary and
    problematic single-use plastics.”

    From: https://www.nytimes.com/2020/10/30/
    The sentence “The study estimates that in 2016, the United States contributed between 1.1 and 2.2 million metric tons of plastic waste to the oceans…” (lines 36-39) contains a/an
    Escolha uma alternativa para a questão 7e5c6294-92
  • 7E5352FD-92

    Inglês

    Interpretação de texto | Reading comprehension
    UECE · 2020DifícilEntre para guardar nos favoritos
    Americans May Add Five Times More Plastic to the Oceans Than Thought

    The United States is using more
    plastic than ever, and waste exported for
    recycling is often mishandled, according
    to a new study.
    The United States contribution
    to coastal plastic pollution worldwide is
    significantly larger than previously
    thought, possibly by as much as five
    times, according to a study published
    Friday. The research, published in Science
    Advances, is the sequel to a 2015 paper
    by the same authors. Two factors
    contributed to the sharp increase:
    Americans are using more plastic than
    ever and the current study included
    pollution generated by United States
    exports of plastic waste, while the earlier
    one did not.
    The United States, which does
    not have sufficient infrastructure to
    handle its recycling demands at home,
    exports about half of its recyclable waste.
    Of the total exported, about 88 percent
    ends up in countries considered to have
    inadequate waste management.
    “When you consider how much
    of our plastic waste isn’t actually
    recyclable because it is low-value,
    contaminated or difficult to process, it’s
    not surprising that a lot of it ends up
    polluting the environment,” said the
    study’s lead author, Kara Lavender Law,
    research professor of oceanography at
    Sea Education Association, in a
    statement.
    The study estimates that in
    2016, the United States contributed
    between 1.1 and 2.2 million metric tons of
    plastic waste to the oceans through a
    combination of littering, dumping and 
    mismanaged exports. At a minimum,
    that’s almost double the total estimated
    waste in the team’s previous study. At the
    high end, it would be a fivefold increase
    over the earlier estimate.
    Nicholas Mallos, a senior
    director at the Ocean Conservancy and an
    author of the study, said the upper
    estimate would be equal to a pile of
    plastic covering the area of the White
    House Lawn and reaching as high as the
    Empire State Building.
    The ranges are wide partly
    because “there’s no real standard for
    being able to provide good quality data on
    collection and disposal of waste in
    general,” said Ted Siegler, a resource
    economist at DSM Environmental
    Solutions, a consulting firm, and an
    author of the study. Mr. Siegler said the
    researchers had evaluated waste-disposal
    practices in countries around the world
    and used their “best professional
    judgment” to determine the lowest and
    highest amounts of plastic waste likely to
    escape into the environment. They settled
    on a range of 25 percent to 75 percent.
    Tony Walker, an associate
    professor at the Dalhousie University
    School for Resource and Environmental
    Studies in Halifax, Nova Scotia, said that
    analyzing waste data can amount to a
    “data minefield” because there are no
    data standards across municipalities.
    Moreover, once plastic waste is shipped
    overseas, he said, data is often not
    recorded at all.
    Nonetheless, Dr. Walker, who
    was not involved in the study, said it
    could offer a more accurate accounting of
    plastic pollution than the previous study,
    which likely underestimated the United
    States’ contribution. “They’ve put their
    best estimate, as accurate as they can be
    with this data,” he said, and used ranges,
    which underscores that the figures are
    estimates.
    Of the plastics that go into the
    United States recycling system, about 9
    percent of the country’s total plastic
    waste, there is no guarantee that they’ll
    be remade into new consumer goods. New
    plastic is so inexpensive to manufacture
    that only certain expensive, high-grade
    plastics are profitable to recycle within the
    United States, which is why roughly half
    of the country’s plastic waste was shipped
    abroad in 2016, the most recent year for
    which data is available.
    Since 2016, however, the
    recycling landscape has changed. China
    and many countries in Southeast Asia
    have stopped accepting plastic waste
    imports. And lower oil prices have further
    reduced the market for recycled plastic.
    “What the new study really underscores is
    we have to get a handle on source
    reduction at home,” Mr. Mallos said. “That
    starts with eliminating unnecessary and
    problematic single-use plastics.”

    From: https://www.nytimes.com/2020/10/30/
    One of the factors that contributes to the huge amount of plastic waste is the fact that
    Escolha uma alternativa para a questão 7e5352fd-92
  • 8C1D6410-05

    Física

    Eletricidade
    FGV · 2020DifícilEntre para guardar nos favoritos
    Uma esfera metálica oca, cujo raio da superfície externa é R, está eletrizada com carga positiva e localizada no vácuo. Considere o ponto X, localizado no centro da esfera, e dois pontos, Y e Z, localizados fora da esfera e distando, respectivamente, R e 3R da superfície externa da esfera. Adotando-se o potencial elétrico como nulo a uma distância infinita da esfera e denominando-se VX, VY e VZ os potenciais elétricos dos pontos X, Y e Z, respectivamente, tem-se:
    Escolha uma alternativa para a questão 8c1d6410-05
  • 8C1A6F4C-05

    Física

    Ondas e Propriedades Ondulatórias
    FGV · 2020DifícilEntre para guardar nos favoritos
    A figura mostra dois recipientes cilíndricos idênticos, R e S, de altura 35 cm, contendo água até diferentes alturas, hR e hS.

    Imagem da questão de Física, FGV 2020, Ondas e Propriedades Ondulatórias

    Colocando-se um alto-falante que emite um som de frequência 850 Hz sobre cada recipiente, separadamente, verifica-se que eles funcionam como tubos sonoros fechados em uma extremidade e abertos na outra, ocorrendo ressonância em ambos. Considerando-se a velocidade de propagação do som no ar igual a 340 m/s, a diferença entre as alturas da água nos dois recipientes, hS – hR, é igual a
    Escolha uma alternativa para a questão 8c1a6f4c-05
  • 8C16E86E-05

    Física

    Ótica
    FGV · 2020DifícilEntre para guardar nos favoritos
    Uma lente convergente de distância focal igual a 6,0 cm é colocada entre duas fontes de luz puntiformes, de modo que fiquem localizadas sobre o eixo principal da lente. Sabendo-se que a distância entre uma das fontes e a lente é 12 cm e que as imagens das duas fontes são coincidentes, a distância entre as fontes de luz é
    Escolha uma alternativa para a questão 8c16e86e-05
  • 8C0FDF99-05

    Física

    Física Térmica - Termologia
    FGV · 2020DifícilEntre para guardar nos favoritos
    Certa massa de gás ideal sofreu três transformações. A primeira, AB, foi isotérmica, a segunda, BC, foi isovolumétrica e a terceira, CA, foi isobárica, como mostra a figura.

    Figura 1 de 2 da questão de Física, FGV 2020, Física Térmica - Termologia

    Considerando-se que o calor absorvido pelo gás seja positivo, que o calor cedido seja negativo, que o trabalho realizado pela força aplicada pelo gás no meio exterior seja positivo e que o trabalho realizado pela força aplicada pelo meio exterior sobre o gás seja negativo, montou-se o quadro a seguir.

    Figura 2 de 2 da questão de Física, FGV 2020, Física Térmica - Termologia

    Completam, respectivamente, as células X, Y e Z do quadro:
    Escolha uma alternativa para a questão 8c0fdf99-05
  • 8C0C04DD-05

    Física

    Física Térmica - Termologia
    FGV · 2020DifícilEntre para guardar nos favoritos
    Dois objetos de materiais, massas e temperaturas diferentes foram colocados no interior de um calorímetro ideal de capacidade térmica desprezível e, após certo tempo, atingiram o equilíbrio térmico. É indubitável que, ao fim desse processo,
    Escolha uma alternativa para a questão 8c0c04dd-05
  • 8BEAD87C-05

    Inglês

    Interpretação de texto | Reading comprehension
    FGV · 2020DifícilEntre para guardar nos favoritos
    Read the text to answer question.

         The formula for calculating people’s environmental footprint is simple, but widely misunderstood: Impact = Population x Affluence x Technology (I = PAT). The global rate of consumption growth, before the pandemic, was 3% a year. Population growth is 1%. Some people assume this means that the rise in population bears one-third of the responsibility for increased consumption. But population growth is overwhelmingly concentrated among the world’s poorest people, who have scarcely any A or T to multiply their P.
         Yet it is widely used as a blanket explanation of environment breakdown. Panic about population growth enables the people most responsible for the impacts of rising consumption (the affluent) to blame those who are least responsible.

    (George Monbiot. www.theguardian.com, 26.08.2020. Adapted.)
    The formula for calculating people’s environmental footprint
    Escolha uma alternativa para a questão 8bead87c-05
  • 8BD8A4F6-05

    Inglês

    Interpretação de texto | Reading comprehension
    FGV · 2020DifícilEntre para guardar nos favoritos
    Read the text and the graphs.

    Bypassed by the rescue

    In a pandemic that’s wreaked widespread economic havoc, Cleveland has been among the hardesthit cities in the U.S. And at a time when the U.S. is engaged in another conversation about its foundational racial inequalities, not much of Washington’ $2 trillion has reached Cleveland’s predominantly Black neighborhoods.


    Imagem da questão de Inglês, FGV 2020, Interpretação de texto | Reading comprehension
    (Bloomberg Businessweek, 20.07.2020. Adapted.)

    By comparing the text and the graphs it is possible to state that
    Escolha uma alternativa para a questão 8bd8a4f6-05
  • 8BD1B5CE-05

    Inglês

    Interpretação de texto | Reading comprehension
    FGV · 2020DifícilEntre para guardar nos favoritos
    Read the text to answer question.

    Imagem da questão de Inglês, FGV 2020, Interpretação de texto | Reading comprehension

         We are at the beginning of a long road to rethinking and rebuilding supply chain models to encompass not just financial priorities but also business operations continuity in the most trying of circumstances. Executives from France and Italy, for example, are discussing ways to remake their businesses in the wake of the Covid-19 pandemic. Their specialty is supply chains. They are smart people at the core of the world’s most sophisticated and valuable systems of manufacture, shipment, and inventory, and yet many of their supply systems staggered in the past few months – the byproduct of reliance on old business models.
    (Antonio Gulli. www.forbes.com, 28.07.2020. Adapted.)
    One problem concerning supply chains after the outbreak of Covid-19 relates to
    Escolha uma alternativa para a questão 8bd1b5ce-05
  • 8BCE6AA0-05

    Inglês

    Interpretação de texto | Reading comprehension
    FGV · 2020DifícilEntre para guardar nos favoritos
    Read the text to answer question.

             It wasn’t the first attempt to deter foreign students, but it could have been the most disruptive. The U.S. Immigration and Customs Enforcement agency sought to bar visas for international students at colleges that offer only virtual instruction. Students on existing visas would have had to transfer to a school that offers at least some in-person teaching if they wanted to remain in the U.S.
         The policy swiftly brought together a broad coalition of colleges, states and businesses that opposed it. “The overwhelming negative reaction to this proposal in a very short period of time shows that the administration really struck a nerve with this,” says Terry Hartle, from the American Council on Education. “It’s unprecedented for that many colleges and universities to file suit against the federal government.”

    (Bloomberg Businessweek, 20.07.2020. Adapted.)
    The expression from the second paragraph “struck a nerve” means, in the context:
    Escolha uma alternativa para a questão 8bce6aa0-05
  • 8BCA2ADF-05

    Inglês

    Interpretação de texto | Reading comprehension
    FGV · 2020DifícilEntre para guardar nos favoritos
    Read the text to answer question.

             It wasn’t the first attempt to deter foreign students, but it could have been the most disruptive. The U.S. Immigration and Customs Enforcement agency sought to bar visas for international students at colleges that offer only virtual instruction. Students on existing visas would have had to transfer to a school that offers at least some in-person teaching if they wanted to remain in the U.S.
         The policy swiftly brought together a broad coalition of colleges, states and businesses that opposed it. “The overwhelming negative reaction to this proposal in a very short period of time shows that the administration really struck a nerve with this,” says Terry Hartle, from the American Council on Education. “It’s unprecedented for that many colleges and universities to file suit against the federal government.”

    (Bloomberg Businessweek, 20.07.2020. Adapted.)
    The expressions from the first paragraph “could have been” and “would have had” help understand that, as to exclusively virtual instruction in U.S. universities and colleges,
    Escolha uma alternativa para a questão 8bca2adf-05
  • 8BC70343-05

    Inglês

    Sinônimos | Synonyms
    FGV · 2020DifícilEntre para guardar nos favoritos
    Read the text to answer question.

    The aliens among us

         Humans think of themselves as the world’s apex predators. Hence the silence of sabre-tooth tigers, the absence of moas from New Zealand and the long list of endangered megafauna. But sars-cov-2 shows how people can also end up as prey. Viruses have caused a litany of modern pandemics, from Covid-19, to hiv/aids to the influenza outbreak in 1918-20, which killed many more people than the first world war. Before that, the colonisation of the Americas by Europeans was abetted – and perhaps made possible – by epidemics of smallpox, measles and influenza brought unwittingly by the invaders, which annihilated many of the original inhabitants.

    (www.economist.com, 22.08.2020. Adapted.)
    In the fragment “epidemics of smallpox, measles and influenza brought unwittingly by the invaders”, the underlined word can be replaced, with no change in meaning, by
    Escolha uma alternativa para a questão 8bc70343-05
  • 8BC3FA56-05

    Inglês

    Interpretação de texto | Reading comprehension
    FGV · 2020DifícilEntre para guardar nos favoritos
    Read the text to answer question.

    The aliens among us

         Humans think of themselves as the world’s apex predators. Hence the silence of sabre-tooth tigers, the absence of moas from New Zealand and the long list of endangered megafauna. But sars-cov-2 shows how people can also end up as prey. Viruses have caused a litany of modern pandemics, from Covid-19, to hiv/aids to the influenza outbreak in 1918-20, which killed many more people than the first world war. Before that, the colonisation of the Americas by Europeans was abetted – and perhaps made possible – by epidemics of smallpox, measles and influenza brought unwittingly by the invaders, which annihilated many of the original inhabitants.

    (www.economist.com, 22.08.2020. Adapted.)
    According to the text,
    Escolha uma alternativa para a questão 8bc3fa56-05
  • 8BC01467-05

    Inglês

    Palavras conectivas | Connective words
    FGV · 2020DifícilEntre para guardar nos favoritos
    Read the text to answer question.

    The aliens among us

         Humans think of themselves as the world’s apex predators. Hence the silence of sabre-tooth tigers, the absence of moas from New Zealand and the long list of endangered megafauna. But sars-cov-2 shows how people can also end up as prey. Viruses have caused a litany of modern pandemics, from Covid-19, to hiv/aids to the influenza outbreak in 1918-20, which killed many more people than the first world war. Before that, the colonisation of the Americas by Europeans was abetted – and perhaps made possible – by epidemics of smallpox, measles and influenza brought unwittingly by the invaders, which annihilated many of the original inhabitants.

    (www.economist.com, 22.08.2020. Adapted.)
    In the second sentence in the text, the term “hence” can be replaced, with no change in meaning, by
    Escolha uma alternativa para a questão 8bc01467-05
  • 6619D0E9-05

    Português

    Flexão de voz (ativa, passiva, reflexiva)
    FGV · 2020DifícilEntre para guardar nos favoritos
    Leia o texto de Teresinha Costa para responder à questão.

         Em História social da criança e da família, Philippe Ariès faz um estudo na Europa, no período compreendido entre a Idade Média e o século XX, para demonstrar como a definição de criança se modificou no decorrer do tempo de acordo com parâmetros ideológicos. Pela análise de pinturas, diários, esculturas e vitrais produzidos na Europa no período anterior aos ideais da Revolução Francesa, Ariès forja a expressão "sentimento da infância" para designar "a consciência da particularidade infantil, essa particularidade que distingue essencialmente a criança do adulto". Esse sentimento vai aparecer a partir apenas do século XVII.
    Na Idade Média, a criança era vista como um pequeno adulto, sem características que a diferenciassem, e desconsiderada como alguém merecedor de cuidados especiais. Isso não significava que as crianças fossem até então desprezadas ou negligenciadas, mas sim que não se tinha consciência de uma série de particularidades intelectuais, comportamentais e emocionais que passaram, então, a ser consideradas como inerentes ou até mesmo naturais às crianças. Ariès comenta, inclusive, que os pintores ocidentais reproduziam crianças vestidas como pequenos adultos, e que somente percebemos se tratar de uma criança devido ao seu tamanho reduzido. Nas sociedades agrárias, a infância era um período rapidamente superado e, tão logo a criança adquiria alguma independência, passava a participar da vida dos adultos e de seus trabalhos, jogos e festas.

    (Psicanálise com crianças, 2010.)
    "Isso não significava que as crianças fossem até então desprezadas" (2° parágrafo)

    Se esta frase for transposta para a voz ativa, a locução verbal sublinhada muda para:
    Escolha uma alternativa para a questão 6619d0e9-05
  • 65E1E27F-05

    Química

    Equilíbrio Químico
    FGV · 2020DifícilEntre para guardar nos favoritos
    O gás monóxido de cloro (ClO) é muito reativo e pode se formar em condições especiais. Na estratosfera, ele dimeriza de acordo com a equação

    2ClO (g) (ClO)2 (g)

    Os dados de reações de dimerização do gás monóxido de cloro em diferentes temperaturas estão indicados na tabela.

    Imagem da questão de Química, FGV 2020, Equilíbrio Químico

    O processo de dimerização do gás monóxido de cloro é
    Escolha uma alternativa para a questão 65e1e27f-05
  • 65C964CE-05

    Química

    Estudo da matéria: substâncias, misturas, processos de separação.
    FGV · 2020DifícilEntre para guardar nos favoritos
    O esquema apresenta o processo de fabricação de ácido fosfórico (H3PO4) a partir da reação do ácido sulfúrico (H2SO4) com a rocha fosfática, que contém preponderantemente fosfato de cálcio (Ca3(PO4)2) e outros contaminantes, representados por seus óxidos.


    Imagem da questão de Química, FGV 2020, Estudo da matéria: substâncias, misturas, processos de separação.
    (Nilson Fernandes et al. “Effect of the impurities on the phosphoric acid process”.
    Materials Science Forum, 2012. Adaptado.)

    A classificação do produto obtido nessa mistura reacional em relação às suas fases e o número total de elétrons do íon metálico bivalente dentre os cátions dos óxidos utilizados na formação da mistura reacional são

    Dados:
    Fe Z = 26
    Al Z = 13
    Mg Z = 12
    Escolha uma alternativa para a questão 65c964ce-05
  • D18B7494-04

    Conhecimentos Gerais

    Conhecimentos Gerais Sobre Arte e Cultura
    FGV · 2020DifícilEntre para guardar nos favoritos
    Observe a montagem visual que faz parte de uma série fotográfica composta entre 1967 e 1972.


    Imagem da questão de Conhecimentos Gerais, FGV 2020, Conhecimentos Gerais Sobre Arte e Cultura
    (Martha Rosler. Cleaning the Drapes, 1967-1972. www.moma.org)

    Vinculando-se o momento da produção da série fotográfica com aquela conjuntura da história norte-americana, a imagem “Limpando a cortina” pode fornecer explicação sobre
    Escolha uma alternativa para a questão d18b7494-04
  • D1841986-04

    História

    História Geral
    FGV · 2020DifícilEntre para guardar nos favoritos
    Lenin tinha como única fonte de informação os jornais estrangeiros, mas, lendo as entrelinhas de suas matérias imprecisas e tendenciosas, pôde apreender os dados fundamentais. [...] O Soviete era o porta-voz do povo, que queria paz, pão, liberdade e terra. O Governo Provisório [...] representava uma burguesia cujas tendências liberais se limitavam à intenção de livrar-se dos Romanov.

    (Edmund Wilson. Rumo à estação Finlândia, 2013.)

    O excerto refere-se à análise feita por Lenin, líder do Partido Bolchevista, do movimento social que derrubou o czar Nicolau II, em março de 1917. No seu entender, havia
    Escolha uma alternativa para a questão d1841986-04