I think the answer is a cell..
17=3
18=4
I'm not that sure about 17, but I think it's right
The types are Blackwater, Graywater and Yellow water.
You can find two types of wastewater: household sewage and wastewater
The answer is in the question. It's called imprinting.
Collenchyma and Parenchyma because they are cellulose containing cells.
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