Marco and Elaine are building a stand like the one shown to display trophies.
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Answer:
68 square feet is the total surface area of the stand.
Step-by-step explanation:
Since both the parts of the stand are in the shape of prism.
Therefore surface area of the stand = surface area of horizontal prism + surface area of vertical prism
Since the formula of surface area of prism = 2(lw + lh + hw)
where l = length, w = width, h = height
Now for horizontal prism
l = 7 ft. , w = 1 ft. , h = 2 ft
Therefore area of horizontal prism = 2(7×1 + 7×2 + 2×1) = 2×23 = 46 square feet
Now dimensions of the vertical prism
l = 3 ft. , w = 2 ft. , h = 1 ft.
and area = 2(3×2 + 3×1 + 1×2) = 2(11) = 22 square feet.
Now the area of whole structure will be = 46 + 22 = 68 square feet.