Chapter 2

A water utility operator needs to determine how many gallons of paint are needed to paint the outside of an above ground storage tank and the cost of the paint. The tank has a 120-foot diameter and is 32 feet tall. (Assume that one gallon of paint can cover \(125 \mathrm{ft}^{2}\) and costs \(\$ 25.75\) per gallon.)

What is the volume in 2,000 feet of 18 -inch diameter pipe?

A rectangular channel flows millions of gallons of water through it and dumps into a storage reservoir. The channel is 2 miles long 3 feet wide and 2 feet deep. What is the area of the channel opening?

A construction crew will be installing 2,500 feet of 18 -inch diameter pipe. The width of the trench will be 40 inches and the depth 45 inches. After the pipe has been installed, how many cubic yards of dirt will be needed to backfill the trench? (Assume the trench will be backfilled up to 8 inches from the ground surface.)

A trapezoidal-shaped channel is 3 feet wide at the bottom and 5 feet wide at the top and the water is 4 feet deep when the channel is full. What is the area of a cross section of the channel?

A sedimentation basin is 100 feet long, 30 feet wide, and 20 feet deep. How many gallons can it hold?

An elevated storage tank is shaped like a sphere and needs to be recoated. If the diameter of the tank is 65 feet, what is the surface area?

What is the surface area of a spherical structure that has a 42 -foot diameter?

A maintenance crew is replacing a 12" meter at a well. The specifications state that there needs to be 3 times the pipe diameter in feet of straight pipe before the meter and 5 times the pipe diameter in feet of straight pipe after the meter. How many feet of \(12^{\prime \prime}\) pipe are needed?

A \(1.25\) -mile section of trapezoidal shaped aqueduct needs to be drained. The aqueduct is 5 feet wide at the base and 10 feet wide at the water line. If there is 9 -acre feet of water in the aqueduct, what is the depth?

A contractor just installed 350 feet of 8 " diameter pipe. They want to wrap a corrosion resistant sleeve around the pipe and fill the pipe to pressure test it. How many gallons of water will the pipe hold and how many square feet of corrosion resistant sleeve are required to cover the whole pipe?

A water utility manager is determining what shaped storage tank should be used to store water for a small mobile home park. The mobile home park needs 110,000 gallons of storage. There is room for a 25 -foot diameter and 30 foot tall cylinder shaped tank or a 30 foot diameter sphere shaped tank. Which tank will provide the adequate storage?