Final answer:
The hiker uses a linear model to represent the elevation during the hike.
Step-by-step explanation:
The subject of this question is Mathematics and the grade level is High School.
The hiker uses a linear model to represent the elevation during the hike. The linear model is y = -290t, where y represents the elevation in feet and t represents the time in hours since the start of the hike.
For example, if the hiker has been hiking for 3 hours, the elevation can be calculated by substituting t = 3 into the equation: y = -290(3) = -870 feet. Therefore, the hiker's elevation after 3 hours is -870 feet.