Find the total surface area.
8 km
4 km
3.9 km
2 km
8 km

Answer:
71.2 km²
Step-by-step explanation:
Triangles: 1/2(8)(3.9)=15.6 (2 of them - front and back)
Base: 8x2=16
Side: 4x2=8
Slant:8x2=16
15.6+15.6+16+8+16=71.2