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Combine the information in the problem and the chart using the average balance method to solve the problem.

An airplane travels at an unknown elevation before it descends 3 miles to an elevation of 15 miles. find the elevation of the plane before its descen.

The perimeter of a rectangular lot of land is 436 ft. this includes an easement of x feet of uniform width inside the lot on which no building can be done. if the buildable area is 122 ft by 60 ft, determine the width of the easement. select one: a. 9 feet b. 18 feet c. 4.5 feet d. 7 feet