Answer: 1350 square cm
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Step-by-step explanation:
Each face of the cube is a square with side length 15. The area of the square is s^2 = 15^2 = 225. There are 6 faces, so 6*225 = 1350
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In terms of a formula, the surface area of a cube is
SA = 6s^2
plugging in s = 15 gives
SA = 6*15^2
SA = 6*225
SA = 1350
Basically it's the same sort of steps as before.