In our Solar System, the planets Mars and Neptune have approximately circular orbits around the Sun. The mean orbital radius of Mars is 1.5 AU1.5\text{ AU}1.5 AU and the mean orbital radius of Neptune is 30.0 AU30.0\text{ AU}30.0 AU.
What is the ratio of the orbital speed of Mars to the orbital speed of Neptune, vMarsvNeptune\displaystyle \frac{v_{\text{Mars}}}{v_{\text{Neptune}}}vNeptunevMars?
202020
4.54.54.5
0.220.220.22
0.0500.0500.050