Which picture?, pls Clip the picture for the answer.
sludge
<span>Sewage treatment is also known as wastewater treatment. It is
a process whereby contaminant is removed from wastewater. Thus, chemical,
biological and physical process are commonly used to remove contaminants from
wastewater and the by-products of wastewater treatment is usually inform of
solid waste known as sewage sludge.</span>
Macromolecules are large molecules within your body that serve essential physiological functions<span>. Encompassing </span>carbohydrates<span>, </span>proteins, lipids and nucleic acids<span>, macromolecules exhibit a number of similarities.
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It is referred to as a selective semipermeable membrane because it only allows certain things through, due to the size and shape of whatever is trying to get through.
