A student found the surface area of this pyramid. Surface area = (12)(6) +
1
2
(12)(8) +
1
2
(6)(9.5)

= 72 + 48 + 28.5

= 148.5cm²

A net has a rectangle at the center and 4 triangles on the sides. The rectangle has a length of 12 centimeters and a height of 6 centimeters. 2 triangles have a base of 12 centimeters and a height of 8 centimeters. 2 triangles have a base of 6 centimeters and a height of 9.5 centimeters.
What error did the student make?
The student should have used the same value for all of the triangular faces.
The student added only three of the five faces.
The student did not use the correct formula to find the area of the triangular faces.
The student did not find the correct area of the rectangular base.