A planet has a volume of $\displaystyle {7.1}\cdot{10}^{{15}}$ km³. One of its moons has a volume of $\displaystyle {6.4}\cdot{10}^{{10}}$ km³. Which of the following most closely approximates how many orders of magnitude more volume the planet has?
NASA: Cassini spacecraft wide-angle camera on 22 May 2015