Take into account that the volume of the code of paint is:
![V=A\cdot w](https://img.qammunity.org/2023/formulas/physics/college/wgx3g6z5iddua89ehlh6ipad7h3uz21ptq.png)
where A is the surface area and w is the thick of the code of paint (w = 10 mm).
Consider that the previous volume V is determined by the amount of pain. In this case, there is 1 gallon of paint, which in units of ft^3 is:
![1\text{gal}=0.1605ft^3](https://img.qammunity.org/2023/formulas/physics/college/ptx2a4jlni4y6jc3z6qen2m9bifjgrolia.png)
Now, consider also that 10mm in units of feet is:
![10mm\cdot(1m)/(1000mm)\cdot(3.28ft)/(1m)=0.0328ft](https://img.qammunity.org/2023/formulas/physics/college/p6n54mzxlxp1r223ppxvpmulet991pg0pi.png)
In the equation V = A*w, solve for A, replace the values of V and w in feet, and simplify:
![A=(V)/(w)=(0.1605ft^3)/(0.0328ft)\approx4.89ft^2](https://img.qammunity.org/2023/formulas/physics/college/3t7t9pxdv7mjm06xhzo874p5dqoxx927r9.png)
Hence, 1 gallon of paint will cover a surface area of approximately 4.89ft^2.