The diagrams below show the stages and equipment used in the cement-making process, and how cement is used to produce concrete for building purposes. Summarise the information by selecting and reporting the main features, and make comparisons where relevant.

The diagrams illustrate how cement is manufactured from raw materials and how it is combined with other ingredients to make concrete.

Overall

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, it is clear from the data that the first process involves five stages,

whereas

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the second is a single mixing step in which the powder forms only a small share of the final product, so the majority of the building material consists of sand and gravel.

According to

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the first graphic, the initial step takes place in a crusher, where limestone and clay are broken into a fine powder.

Next,

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this

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material passes through a mixer, after which it enters a rotating heater, so the temperature rises sharply to roughly 1,400 degrees.

Subsequently

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, the heated substance is ground again, and the resulting product is packed into bags, each of which amounts to around 50 kilograms. The second graphic,

in contrast

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, shows that four components are blended in fixed percentages. Gravel constitutes the largest portion at 50 per cent, closely followed by sand at approximately a quarter,

while

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cement and water trail far behind and register a mere 15 and 10, respectively.

Furthermore

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, these are rotated together in a drum.

Finally

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, if these quantities were altered considerably, the concrete would not set properly.