The Moon requires $27$ days to complete one orbit around the Earth. The mean radius of the Moon's orbit is $3.8 \times 10^8\,\text{m}$. What is the Moon's average orbital speed?
- A$160\,\text{m s}^{-1}$
- B$1000\,\text{m s}^{-1}$
- C$1.4 \times 10^8\,\text{m s}^{-1}$
- D$8.8 \times 10^8\,\text{m s}^{-1}$