Answer:
Step-by-step explanation:
The lateral surface area is the combined area of the three rectangular faces of the prism
Each rectangular face has a base 12 cm and a height of 9 cm. So surface area of each of the rectangular areas is the same
Each rectangular face surface area = 12 x 9 = 108 cm²
Lateral surface area L = x 108 = 324 cm²
The top and bottom area are triangles each with an area = 1/2 base x height
Total area of triangular faces = 2 x 1/2 x base x height
= base x height
= 9 x 7.8
= 70.2 cm²
Total Surface Area S = 324 + 70.2 = 394.2 cm²
