Final answer:
Mai gained elevation throughout her entire 40-minute hike up the trail.
Step-by-step explanation:
When Mai hiked up the trail, she gained elevation during the entire 40-minute duration of her hike.
Elevation refers to the height above a reference point, such as sea level. In this case, if we consider sea level as the reference point, Mai gained elevation as she climbed up the trail. The time period where she gained elevation is the entire duration of her hike, which is 40 minutes.
During this time period, Mai was exerting energy and overcoming the force of gravity to climb up the trail, which resulted in an increase in her elevation.