Solve the problem. See Example 9.Depth and flow. When the depth of the water in the Tangip...

Solve the problem. See Example 9.

Depth and flow. When the depth of the water in the Tangipahoa River at Robert, Louisiana, is 9.14 feet, the flow is 1230 cubic feet per second (ft3/sec). When the depth is 7.84 feet, the flow is 826 ft3/sec. (U.S. Geological Survey, www.usgs.gov.) Let w represent the flow in cubic feet per second and d represent the depth in feet.

a) Write the equation of the line through (9.14, 1230) and (7.84, 826) and express w in terms of d. Round to two decimal places.

b) What is the flow when the depth is 8.25 ft?

c) Is the flow increasing or decreasing as the depth increases?

Figure for Exercise 101