Answer:
442 ft^3
Explanation:
Find the floor area
rectangle 10 x 6 = 60 ft ^2
two triangles 2 * 1/2 * 3 * sqrt7 = 3 sqrt 7 ft^2
(use pyhtagorean theorem to find height of the triangle = sqrt 7)
Total area * height = volume
(60 + 3 sqrt7) * 6.5 = 441.59 ~~ 442 ft^3