“A continuous electric current of 2,000 amps is to be transmitted from a generator to a transformer located 230 feet away. A copper conductor can be installed for $5.2 per pound, will have an estimated life of 22 years, and can be salvaged for $1 per pound. Power loss from the conductor will be inversely proportional to the cross-sectional area of the conductor. The power loss in one hour may be expressed as 6.76/A kilowatt, where A is the cross-sectional area of the conductor in square inches. The cost of energy is $0.0781 per kilowatt-hour, the interest rate is 9.8%, and the density of copper is 555 pounds per cubic foot. Calculate the optimum cross-sectional area of the conductor. You should assume the conductor operates 24 hours a day, 365 days per year.”