Answer:
C: 495ft²
Step-by-step explanation:
You need to calculate and add the surface area of the three rectangular faces of this prism. The two triangular ends are not covered in the foil as stated in the question. You find this like any other rectangle by multiplying the length by the width. (a = lw)
Let's start with the bottom rectangle, it has dimensions of 5x 16.5ft
5 * 16.5 = 82.5
Now the rectangle on the right side.
13 * 16.5 = 214.5
Now the left or back side rectangle.
12 * 16.5 = 198
Now add these values together
82.5 + 214.5 + 198 = 495ft²