Answer:
78 in² (Choice B)
Explanation:
Since they have exploded the 3-D cuboid into 2-D, it is easier to compute
Looking at the 2-D version you can see 4 rectangles each 3" x 5"
At the bottom on each side are 2 squares each 3" x 3"
Area of a rectangle = l x w
In this case, area of each rectangle = 3 x 5 = 15
Since there are 4 rectangles, total area of these four = 4 x 15 = 60 in²
Each square is area 3" x 3" = 9"
Since there are 2 such squares, total area of these two = 9 x 2 = 18in²
Total area of the 2-D blowup which is the same as the Surface Area of the prism = 60 in² + 18in² = 78 in²