Amount of gift wrap to cover the entire box = total surface area of rectangular box = 1,048 in.².
The total surface area of a rectangular box is the area of all the faces of the box = 2(wl + hl + hw).
Therefore, to find the material that will cover the whole rectangular box, Demarcus should find its total surface area, given the following dimensions:
Plug in the values into TSA = 2(wl + hl + hw):
Total surface area of rectangular box = 2(8×20 + 13×20 + 13×8) = 1,048 in.²
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