Final answer:
The change in Vivian's elevation from the bottom to the top of the Ferris wheel is a positive number because that motion represents an increase in height or upward displacement.
Step-by-step explanation:
The change in Vivian's elevation from the bottom of the Ferris wheel to the top represents a change in vertical position. In physics, an upward movement is typically considered to have a positive displacement. Therefore, the answer to whether the change in Vivian's elevation is a positive or a negative number is A. Positive; because she went up.
When considering movement, it's essential to understand the direction in relation to a chosen point of reference. Movement upwards from a lower point implies an increase in elevation, which is quantified as a positive value. This is similar to how in physics, an object thrown upwards has an initial positive velocity, and its maximum height is seen as a positive displacement, despite the constant negative acceleration due to gravity acting on it.
Therefore, even if Vivian started at a negative elevation or below sea level, her movement to the top of the Ferris wheel is considered positive because she is moving away from the ground towards a higher point.