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**HallsofIvy** First find the length of the conduit, using the Pythagorean theorem: vertically, it is 3000 feet long and,since it rises 16 feet per 1000 horizontal feet, it rises 3(16)= 48. The conduit itself is the hypotenuse of a right triangle with legs of length 3000 and 48- its length is [tex]\sqrt{3000^2+ 48^2}.

Now think of the cross section as two circles. The inner circle has radius 10 and the outer circle has radius 1. Find the areas of those two circles and subtract to find the area between them. Multiply that area by the length of the conduit.