While exploring a volcano, Zane heard some rumbling, so he decided to climb up out of there as quickly as he could. Zane's elevation relative to the edge of the inside of the volcano (in meters) as a function of time (in seconds) is graphed. 10 15 20 25 30 35 -10 -15+ -20 -25- Time (seconds) Over any given period of seven seconds, Zane climbed meters. (Answer as a number.) Elevation (meters) AO