Figure 19 shows a contour map for the depth of a river between a dam and a bridge. Approximate the volume of water between the dam and the bridge. Hint: Slice the river into eleven 100-feet sections parallel to the bridge and assume that cross-sections are isosceles triangles. The river is approximately 300 feet wide by the dam and 175 feet wide by the bridge.

Dam Bridge 10 ft -40 ft 30 ft loft 20 ft 1100 ft