For this case we have by definition, that the volume of a cone is given by:
![V = \frac {1} {3} * \pi * r ^ 2 * h](https://img.qammunity.org/2020/formulas/mathematics/college/2jq6xkuzqoewsrl22n1svajkh5svl3vxg4.png)
Where:
A: It is the cone radius
h: It's the height
They tell us that the diameter is 21 m, then the radius is half the diameter, that is: 10.5m. The height is 4m. Substituting the data:
.
Finally, the volume of the cube is
![147 \pi \ m ^ 3](https://img.qammunity.org/2020/formulas/mathematics/high-school/s20n1xrqdhuwp1jq79c06x142q6lupjrwa.png)
ANswer:
Option B