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O Brasil é o maior produtor de etanol (C2H60) de cana-de-açúcar do mundo e ocupa posição de liderança na tecnologia de sua produção. Os avanços tecnológicos permitem que a produtividade seja destacada e os custos de produção bem inferiores aos dos concorrentes internacionais.
(fonte: http://www.fapesp.br/materia/2919, acesso em 06 de novembro de 2010.)
O etanol sofre combustão segundo a reação:
A entalpia padrão de combustão de etanol líquido é -1367 kJ/mol. Considerando uma reação de combustão de 1
mol de etanol, com rendimento de 100%, é correto afirmar que ocorre:
A questão deve ser respondida de acordo com o seguinte texto:
A gasolina é constituída por uma mistura de hidrocarbonetos voláteis, predominando o 2,2,3-trimetilpentano e o n-heptano. Em um motor automotivo, uma mistura de ar e vapor de gasolina é comprimida por um pistão e depois incendiada por uma centelha elétrica. A queima de gasolina deve criar uma expansão de gás forte e regular, forçando o pistão para cima e fornecendo força ao longo do eixo acionador do motor, gerando movimento.
Considerando a reação mencionada no texto, é correto afirmar que:A questão deve ser respondida de acordo com o seguinte texto:
A gasolina é constituída por uma mistura de hidrocarbonetos voláteis, predominando o 2,2,3-trimetilpentano e o n-heptano. Em um motor automotivo, uma mistura de ar e vapor de gasolina é comprimida por um pistão e depois incendiada por uma centelha elétrica. A queima de gasolina deve criar uma expansão de gás forte e regular, forçando o pistão para cima e fornecendo força ao longo do eixo acionador do motor, gerando movimento.
Sobre os principais constituintes da gasolina citados, é correto afirmar que:THE NEW ‘OS’ WARS: WINNERS AND LOSERS
By: Tim Bajarin (10.29.2010)
The new OS war will be between operating systems that can work on all types of digital screens.
For decades, when people talked about OS wars, they were mostly referring to the Windows vs. Mac battle. These two operating systems have dominated the PC landscape with Windows owning about 90 percent of the market. This OS war has been great for the PC industry, because as Apple continues to innovate on its OS platform, it forces Microsoft to innovate as well, and in turn, consumers constantly receive new and more powerful OS platforms for their PCs.
Now there is a another OS war developing around smartphones, and if you think the PC OS wars were nasty, just wait for this OS war to heat up. We've already seen charged rhetoric from Apple CEO Steve Jobs over the iPhone, Andy Rubin at Google defending Android against the competition, and RIM's CEO Jim Balsillie ranting about Jobs and company during the iPhone antenna dilemma. All of these folks realize that the stakes are very high and that they need to do whatever is necessary to keep the market looking at them and pushing their platforms forward. To put these OS stakes into perspective, market researchers say that 1.2 billion cell phones will be sold worldwide this year. And while smartphones represent only 22 percent of the cell phone market for 2010, they will make up 60 percent of the market in the U.S. by 2012 and 65 percent of all cell phones sold worldwide will be smartphones by 2015. That means that by 2015 we could see as many as 750 million smartphones sold around the world, which is a massive market and will create amazing market opportunities.
Source: http://www.pcmag.com/article2/0,2817,2371776,00.asp, accessed on November 4, 2010.
As previsões estatísticas apresentadas no trecho acima dizem que:THE NEW ‘OS’ WARS: WINNERS AND LOSERS
By: Tim Bajarin (10.29.2010)
The new OS war will be between operating systems that can work on all types of digital screens.
For decades, when people talked about OS wars, they were mostly referring to the Windows vs. Mac battle. These two operating systems have dominated the PC landscape with Windows owning about 90 percent of the market. This OS war has been great for the PC industry, because as Apple continues to innovate on its OS platform, it forces Microsoft to innovate as well, and in turn, consumers constantly receive new and more powerful OS platforms for their PCs.
Now there is a another OS war developing around smartphones, and if you think the PC OS wars were nasty, just wait for this OS war to heat up. We've already seen charged rhetoric from Apple CEO Steve Jobs over the iPhone, Andy Rubin at Google defending Android against the competition, and RIM's CEO Jim Balsillie ranting about Jobs and company during the iPhone antenna dilemma. All of these folks realize that the stakes are very high and that they need to do whatever is necessary to keep the market looking at them and pushing their platforms forward. To put these OS stakes into perspective, market researchers say that 1.2 billion cell phones will be sold worldwide this year. And while smartphones represent only 22 percent of the cell phone market for 2010, they will make up 60 percent of the market in the U.S. by 2012 and 65 percent of all cell phones sold worldwide will be smartphones by 2015. That means that by 2015 we could see as many as 750 million smartphones sold around the world, which is a massive market and will create amazing market opportunities.
Source: http://www.pcmag.com/article2/0,2817,2371776,00.asp, accessed on November 4, 2010.
Rewrite the bold type sentence without missing its meaning: it forces Microsoft to innovate as well.GOOGLE TV: BOOM OR BUST
By: Tim Bajarin (10.18.2010)
The industry has been trying to bring IPTV to your TV since 1997. What makes Google and its partners think they'll be successful?
I have a question for you. Do you want to view the Internet on your TV? With all of the activity in IPTV these days, this is one of the key questions that is at the heart of whether IPTV eventually succeeds or fails. Since TVs were invented, we have been trained to sit in front of them and consume not interact with them. And only recently have we had to multitask with our TV. Even though we've had picture in picture for years, it took news scrolls at the bottom of our TV screens to train our brains. So, how will consumers integrate the new and even more complex IPTV features into their TV viewing experience?
One of the traits of consumers that has emboldened the IPTV crowd to push forward is the fact that many people sit on their couch and use their laptops or tablets while watching TV. They reason that if they multi-task in this fashion, they may be willing do it on the bigger screen. While I accept the fact that people may want Internet content, such as movies, TV shows, YouTube, etc. on their TV screens, it is quite a leap to assume that people also want to read their newspapers and magazines or view Web sites on a big-screen TV.
Source: http://www.pcmag.com/article2/0,2817,2370894,00.asp, accessed on November 4, 2010.
According to the passage above:Leia as afirmações sobre Morte e vida Severina, de João Cabral de Melo Neto.
I - Em toda a narrativa, Severino participa como um espectador desde a sua saída da Serra da Costela até chegar ao seu porto seguro, que é a cidade de Recife.
II - Os fatos narrados são marcados pela morte, até o momento do nascimento do filho do mestre carpina, o que prenuncia a esperança de uma vida nova.
III - A linguagem da narrativa é elaborada com precisão, realista, concreta, como se pode perceber no fragmento “Só os roçados da morte/compensam aqui cultivar,/e cultivá-los é fácil:/simples questão de plantar;/ não se precisa de limpa,/ de adubar nem de regar;/ as estiagens e as pragas” [...], em que vê claramente a privação do retirante em ter uma qualidade de vida.
IV - O título da obra é um contraponto partindo-se da premissa de que antes da vida vem a morte, porém a inversão no auto é proposital, para mostrar a miséria e a falta de perspectiva do homem nordestino.
Assinale a alternativa correta sobre as afirmações:
Leia o texto para responder a questão
Em relação ao texto e ao contexto literário, pode-se afirmar que:
