The diagram shows the process of dirty water being passed through a simple water filter until it finally comes out as clean water.
Initially, dirty, muddy water is poured out of what appears to be a clear glass into the open end of a dear container. The first section of the large container that the dirty water reaches is a layer of filter paper.
The water passes through the filter paper and continues on downward to pass through the next layer of filtration - gravel and small rocks. Once it has passed through this layer, it continues on to the next layer - fine sand.
The last layer of filtration which follows is a cotton wool filter. Once the water has passed through this layer it finally appears as dean water.
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