The diagram below shows how a biofuel called ethanol is produced.

The picture illustrates the cycle of producing biofuel (ethanol). As shown, there are several distinct stages in

this

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process, from the initial natural sources to the final generation of carbon dioxide.

It is clear that

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in the first stage, many plants and trees grow, and are

then

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harvested by agricultural machines in the second stage. In the next step, these harvested materials go through pre-processing and become cellulose.

At

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In

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the fifth stage, cellulose is processed in factories and converted into sugars. In the

last

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part of

this

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process, sugars are added to microbes.

Following

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this

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, they are remixed to produce ethanol. Afterwards, ethanol is used in a wide range of transportation and vehicles,

such

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as cars, trucks, and

airplanes

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aeroplanes

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, all of which generate a significant amount of carbon dioxide.

Next,

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carbon dioxide and sunlight serve as energy for forests and plants.

This

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cycle

then

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begins again from the first step.