To solve this problem you must apply the proccedure shown below:
1. You have the following information given in the problem above: The regular octahedron with edges that are 2.1 inches.
2. Therefore, you must apply the formula for calculate the volume of a octahedron, which is:
V=(a^3√2)/3
3. Therefore, you have:
V=((2.1 inches)^3√2)/3
V=178.30 inches^3