Todas as questões do ENEM

A listagem numérica abaixo apresentada foi construída com números inteiros positivos seguindo uma lógica própria.

L1; 1

L2; 1, 4

L3; 1, 4, 9

L4; 1, 4, 9, 16

L5; 1, 4, 9, 16, 25

....................................

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O número que está na posição central da linha 2021 é 

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Reducing food waste would mitigate climate change, study shows

April 7, 2016

    Reducing food waste around the world would help curb emissions of planet-warming gases, lessening some of the impacts of climate change such as more extreme weather and rising seas, scientists said on Thursday.
    Up to 14% of emissions from agriculture in 2050 could be avoided by managing food use and distribution better, according to a new study from the Potsdam Institute for Climate Impact Research (PIK). “Agriculture is a major driver of climate change, accounting for more than 20% of overall global greenhouse gas emissions in 2010,” said co-author Prajal Pradhan. “Avoiding food loss and waste would therefore avoid unnecessary greenhouse gas emissions and help mitigate climate change.”
    Between 30 and 40% of food produced around the world is never eaten, because it is spoiled after harvest and during transportation, or thrown away by shops and consumers. The share of food wasted is expected to increase drastically if emerging economies like China and India adopt western food habits, including a shift to eating more meat, the researchers warned. Richer countries tend to consume more food than is healthy or simply waste it, they noted.
    As poorer countries develop and the world’s population grows, emissions associated with food waste could soar from 0.5 gigatonnes (GT) of carbon dioxide equivalent per year to between 1.9 and 2.5 GT annually by mid-century, showed the study published in the Environmental Science & Technology journal. It is widely argued that cutting food waste and distributing the world’s surplus food where it is needed could help tackle hunger in places that do not have enough - especially given that land to expand farming is limited.
    But Jürgen Kropp, another of the study’s co-authors and PIK’s head of climate change and development, told the Thomson Reuters Foundation the potential for food waste curbs to reduce emissions should be given more attention. “It is not a strategy of governments at the moment,” he said.

             (www.theguardian.com. Adaptado.)

Um motorista imprudente, ao dirigir um veículo popular de massa total (veículo + motorista) igual a 2 toneladas, recebe uma mensagem em seu celular e choca-se a 36 km/h com um poste de massa considerada infinita.

Podemos afirmar que a energia liberada nesse choque equivale à energia liberada pela queda de uma pessoa de 100 kg de massa do topo de um edifício de, aproximadamente,

Considere:

aceleração gravitacional g = 10 m/s² ;

altura de cada andar do edifício h = 3 metros.

Considere a matriz , onde x e y são números reais. Se M2 = M.M, então, o determinante de M2 é igual a

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Reducing food waste would mitigate climate change, study shows

April 7, 2016

    Reducing food waste around the world would help curb emissions of planet-warming gases, lessening some of the impacts of climate change such as more extreme weather and rising seas, scientists said on Thursday.
    Up to 14% of emissions from agriculture in 2050 could be avoided by managing food use and distribution better, according to a new study from the Potsdam Institute for Climate Impact Research (PIK). “Agriculture is a major driver of climate change, accounting for more than 20% of overall global greenhouse gas emissions in 2010,” said co-author Prajal Pradhan. “Avoiding food loss and waste would therefore avoid unnecessary greenhouse gas emissions and help mitigate climate change.”
    Between 30 and 40% of food produced around the world is never eaten, because it is spoiled after harvest and during transportation, or thrown away by shops and consumers. The share of food wasted is expected to increase drastically if emerging economies like China and India adopt western food habits, including a shift to eating more meat, the researchers warned. Richer countries tend to consume more food than is healthy or simply waste it, they noted.
    As poorer countries develop and the world’s population grows, emissions associated with food waste could soar from 0.5 gigatonnes (GT) of carbon dioxide equivalent per year to between 1.9 and 2.5 GT annually by mid-century, showed the study published in the Environmental Science & Technology journal. It is widely argued that cutting food waste and distributing the world’s surplus food where it is needed could help tackle hunger in places that do not have enough - especially given that land to expand farming is limited.
    But Jürgen Kropp, another of the study’s co-authors and PIK’s head of climate change and development, told the Thomson Reuters Foundation the potential for food waste curbs to reduce emissions should be given more attention. “It is not a strategy of governments at the moment,” he said.

             (www.theguardian.com. Adaptado.)

O aplicativo Waze, instalado em tablets e smartphones, tem sido usado com frequência para auxiliar os motoristas a “fugirem” do trânsito pesado das grandes cidades. Esse aplicativo consegue apresentar ao usuário uma boa rota alternativa e o tempo estimado para chegada ao destino, baseando-se tão somente nas distâncias e velocidades médias dos diversos usuários nessas rotas.

Suponha que um candidato da FATEC saia de casa às 11 h 10 min. Ele se dirige ao local de realização da prova, iniciando pelo trecho A, de 18 km, e finalizando pelo trecho B, de 3 km, às velocidades médias apresentadas na tela do aplicativo (conforme a figura).

Figura fora de escala.

É correto afirmar que a hora estimada para chegada ao destino é

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Reducing food waste would mitigate climate change, study shows

April 7, 2016

    Reducing food waste around the world would help curb emissions of planet-warming gases, lessening some of the impacts of climate change such as more extreme weather and rising seas, scientists said on Thursday.
    Up to 14% of emissions from agriculture in 2050 could be avoided by managing food use and distribution better, according to a new study from the Potsdam Institute for Climate Impact Research (PIK). “Agriculture is a major driver of climate change, accounting for more than 20% of overall global greenhouse gas emissions in 2010,” said co-author Prajal Pradhan. “Avoiding food loss and waste would therefore avoid unnecessary greenhouse gas emissions and help mitigate climate change.”
    Between 30 and 40% of food produced around the world is never eaten, because it is spoiled after harvest and during transportation, or thrown away by shops and consumers. The share of food wasted is expected to increase drastically if emerging economies like China and India adopt western food habits, including a shift to eating more meat, the researchers warned. Richer countries tend to consume more food than is healthy or simply waste it, they noted.
    As poorer countries develop and the world’s population grows, emissions associated with food waste could soar from 0.5 gigatonnes (GT) of carbon dioxide equivalent per year to between 1.9 and 2.5 GT annually by mid-century, showed the study published in the Environmental Science & Technology journal. It is widely argued that cutting food waste and distributing the world’s surplus food where it is needed could help tackle hunger in places that do not have enough - especially given that land to expand farming is limited.
    But Jürgen Kropp, another of the study’s co-authors and PIK’s head of climate change and development, told the Thomson Reuters Foundation the potential for food waste curbs to reduce emissions should be given more attention. “It is not a strategy of governments at the moment,” he said.

             (www.theguardian.com. Adaptado.)

Sabendo que a medida da área do círculo circunscrito a uma das faces de um tetraedro regular é igual a 9,42 m2 , é correto dizer que a medida, em m2 , da área desse tetraedro (soma das medidas das áreas de suas faces) é

Use o número racional 3,14 como aproximação do número π.

O projeto Mars One pretende colonizar o planeta Marte até 2018. Para tanto, já fez uma pré-seleção de 1 058 pessoas, inclusive do Brasil, para uma viagem de aproximadamente sete meses, somente de ida. O desafio consistirá em viver e trabalhar em habitats especiais e devidamente projetados, cultivando o próprio alimento, buscando água e gelo no solo e fontes de energia alternativas para geração de eletricidade, além da previamente estabelecida.

A escolha da energia a ser utilizada inicialmente foi a que despendesse o menor trabalho no transporte de seu equipamento até o planeta e consequente montagem no local.

Assim sendo, é correto afirmar que a fonte de energia que será inicialmente utilizada é a