If You Monitor Saturn's Atmosphere and You See a Storm

Multiple Choice

If you monitor Saturn's atmosphere and you see a storm near its equator at a longitude of 0° west on one day and at a longitude of 90° west three days later, what is the average wind speed on Saturn at this storm's latitude? Note that these positions are measured on a coordinate system that rotates with the planet's interior, and the radius of Saturn is 6 *10⁷ m.

A) 720 m/s
B) 120 m/s
C) 360 m/s
D) 540 m/s
E) 1,440 m/s