Answer: Ans b.
Vol_total
= 7800 yd^3
Explanation:
The bottom part of your shape is a box, basically (rectangular prism) and the volume is:
V=
length×width×height
Those numbers are all given. Because it is a box shape, it doesn't matter which number is which.
V = 22 × 15 × 16
= 5280 yd^3
Now the "roof" part on top is a little bit different. It is a triangular prism. So the side that needs to be the Base of the prism is the front (or back) triangle.
The volume is:
V
= BaseArea×height
= Area_triangle× ht
= 1/2 bh × height
= 1/2•21•16 × 15
The key to understanding is knowing the triangle must be the base. And the roof line running front to back will be the height. And also understanding the difference between the height of just a triangle (21) and the height of the prism(15). They are different.
Vol_roof = 2520
Then add them together.
Vol_total
= 5280 + 2520
= 7800 yards cubed