Find the Orbital Speed of an Ice Cube in the Rings

Multiple Choice

Find the orbital speed of an ice cube in the rings of Saturn. The mass of Saturn is $5.68 \times 10 ^ { 26 } \mathrm {~kg}$ and use an orbital radius of $1.00 \times 10 ^ { 5 } \mathrm {~km} \cdot \left( \mathrm { G } = 6.67 \times 10 ^ { - 11 } \mathrm {~N} \cdot \mathrm { m } ^ { 2 } / \mathrm { kg } ^ { 2 } \right)$

A) 9.40 km/s
B) 19.5 km/s
C) 13.8 km/s
D) 27.5 km/s