1. Calculate the radius from the diameter:
r = \frac{2000}{2} = 1000 \text{ miles}
2. Substitute the radius into the volume formula:
V = \frac{4}{3} \pi (1000)^3
3. Calculate the volume:
V \approx 4188790204.79 \text{ cubic miles}
The volume is approximately 4188790204.79 \text{ cubic miles} .