Answer 1

Let the edge of the cube be l cm.
Total surface area of the cube = 864 cm²
∴ 6l² = 864 cm²

⇒ l² = `864/6` = 144 

⇒ l = `sqrt 144` = 12 cm

∴ Volume of the cube = l³ = (12)³ = 1728 cm³
Thus, the volume of the cube is 1728 cm³.