The provided chart depicted information about how to converting dirty water to clean water.
Looking at the graph from an overall perspection, it can be seen easily that this process has four main steps, beginning with pouring water into a plastic barrel and ending with having a glass of fresh water.
The first step is that worker will pour a container which is contained dirty water into a plastic barrel and a plastic lid is used to cover the barrel before starting the process of water-filter assembly. Inside this box will be divided into four parts, containing four different substances: unclean water, sand, charcoal and gravel, respectively. This stage is in order to remove some impurities existing in water.
Once toxic substances are cleared, water will be pushed through a small tube connecting the plastic barrel with a storage drum. And eventually, people can be able to use clean water for domestic purpose, such as drinking.