Answer: The graph is attached below.
Step-by-step explanation: Given that when Zane was 20 meters below the edge of a volcano, he heard some rumbling, so he decided to climb up out of there as quickly as he could.
He managed to climb up 4 meters each second and get out of the volcano safely.
We are to graph Zane's elevation relative to the edge of the volcano (in meters) as a function of time (in seconds).
Let, 't' represents the time (along X-axis) and f(t) represents Zane's elevation relative to the edge of the volcano(along Y-axis).
When t = 0, then f(t) = 20.
When t = 1, then f(t) = 20 - 4 = 16.
So, (0, 20) and (1, 16) are two points on the graph.
The slope of the line joining (0, 20) and (1, 16) is

Therefore, the equation of the line will be

The graph of Zane's elevation relative to the edge of the volcano (in meters) as a function of time (in seconds) is shown in the attached figure.