Hello
The volume occupied by the paint is 1 liter, which corresponds to [tex]V=10^{-3}~m^3[/tex].
The volume of the paint is also the product between the covered area A and the the thickness t of the layer of paint:
[tex]V=A t[/tex]
We know the area, [tex]A=10~m^2[/tex], and the volume, so we can calculate the thickness of the layer:
[tex]t= \frac{V}{A}= \frac{10^{-3}~m^3}{10~m^2}=10^{-4}~m [/tex]
