Question

$\huge\mathfrak\red{Answer \: me}$
answer me now only​

Answer 1

Answer:

we have to know the story

then we answer it right?

how can we ans. with out knowing the story

Answer 2

Explanation:

The residue that accumulates in sewage treatment plants is called sludge (or biosolids). Sewage sludge is the solid, semisolid, or slurry residual material that is produced as a by-product of wastewater treatment processes. ... Quite often the sludges are combined together for further treatment and disposal.