The term "elevation" is often used to describe the height of a place (such as city, a mountain, or a valley) compared to sea level. For example, the city of Houston, Texas has an elevation of 105 feet. The surface of the sea has an elevation of 0 feet. Some places are below sea level, so their elevations are negative values. Function f gives the vertical distance of each town from sea level. Both e and f(e) are measured in feet. Complete the table of values.