the water, a fish swims back up 30 feet. Use a number line to help you create an equation that shows the new location of the fish in relation to the water's surface . 0 Interpret the sum in the context of the problem. OA. The equation is - 50 + (- 30) = - 80 . The fish is 80 feet below the water's surface B. The equation is - 50 + 30 = - 20 . The fish is 20 feet below the water's surface C. The equation is - 50 + 30 = - 80 . The fish is 80 feet below the water's surface . D. The equation is - 50 + (- 30) = - 20 . The fish is 20 feet below the water's surface