The side of a square metal sheet is 12 m. Four squares each of side 3 m are cut and removed from the four corners of the sheet and the remaining part is folded to form a cuboid (without top face). Find the volume of the cuboid so formed.
A. `108m^(3)`
B. `36m^(3)`
C. `118m^(3)`
D. `54m^(3)`