To solve this problem you first start out at an elevation of -418 ft. To ascend you add 387 to -418 to get -31 ft. Next, he descends to an elevation that is 94 ft higher than -418 ft. To get this you add 94 ft to -418 to get -324 ft. Finally, he descended 132 ft so subtract 132 from -324 to get a final elevation of -456 ft.
