[tex]\text{Hello there! :)}[/tex]
[tex]\large\boxed{V = 800cm^{3} }[/tex]
[tex]\text{Formula for the volume of a rectangular prism:}\\\\V = l * w * h\\\\\text{In this instance:}\\\\l = 40 cm\\w = 20 cm\\h = 10cm\\\\\text{Use the formula to solve for the volume:}\\V = 40 * 10 * 2\\\\V = 800cm^{3}[/tex]