Answer:
480 ft²
Explanation:
There are 9 polygons whose areas need to be added.
1 square bottom face of prism: 10 ft × 10 ft = 100 ft²
4 rectangular lateral faces of prism: 4 × 10 ft × 6 ft = 240 ft²
4 triangular lateral faces of prism: 4 × (1/2) × 10 ft × 7 ft = 140 ft²
Total = 480 ft²