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marim
One gallon of paint (volume = 3.78 10-3 m3) covers an area of 20.0 m2. What is the thickness of the fresh paint on the wall?
You know the volume of paint, and you know the area that it covers. Volume is essentially \(l * w * h\), and area is \(l*w\), so divide volume by area and you've got the thickness of the coat of paint, in meters