Multiple choice general knowledge math & puzzles surface area of a cube 6 a*a 8 a*a 2 a*a 4 a*a Reveal answer Fill a bubble to check yourself A Correct answer Explanation A cube has six identical square faces. If the side length is 'a', the area of one face is a*a. The total surface area is the sum of all six faces, which is 6 * a^2.