Answer: 433.5 square cm
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Step-by-step explanation:
A cube has 6 identical faces, all of which are squares.
Each square has a side length of 8.5 cm, so its area is (8.5)^2 = 72.25 sq cm.
The overall surface area, aka the area of all 6 faces combined, is 6*72.25 = 433.5 square cm