Final answer:
The change in Vivian's elevation from the bottom of the Ferris wheel to the top is a positive number because she moved higher above sea level.
Step-by-step explanation:
The change in Vivian's elevation from the bottom of the Ferris wheel to the top is a positive number. This is because she moved higher above sea level. When Vivian is at the bottom of the Ferris wheel, her altitude is at its lowest point. As she moves up, her altitude increases, resulting in a positive change in elevation.