Vivian is at a fair in Coachella Valley, California. Much of the valley lies below sea level. Vivian has brought along an altime
ter to measure her elevation at different places in the valley. Vivian's first ride was on the Ferris whizel. When she sat on the wheel at its lowest point her altimeter read -9.6 feet. When she reached the top of the wheel, her altimeter read 12.3 feet. Complete the following steps to calculate the change In Vivian's elevation from the bottom of the Ferris wheel to the top.
