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The diagram below shows the stage and equipment used in the cement‐making process, and how cement is used to produce concrete for building purposes. The diagram illustrates the steps of cement and concrete production from the raw materials. A glance at the diagram pictures that a series of steps need to be taken before concrete is produced. The schema depicts that five different phases of cement production. Initially, limestone and clay are ground diminish by a crusher and then the a mixture of them will be guided into the mixer. After that, the powder of clay and limestone flow to the rotating heater in order to get exposed to by fire flame. Now the compound is in the form of paste. In the next step, the paste is going to being blended by grinder. Finally, the cement is packed and marketed for selling and also utilized in concrete production. Respectively, the ratios of cement (15%), water (10%), sand (25%) and gravel (50%) will be combined with each other in a concrete mixer in order to make a concrete from cement. Overall, these two diagrams differ (vary) in the number of production stages. Further, we should consider the prices proportion of materials in producing concrete. In addition, the mechanism of cement production is more complicated harder than (is more formidable) the concrete production. (you had better not discuss the price)