P2.008 a steel cable is used to support an elevator cage at the bottom of a 1800-ft-deep mineshaft. a uniform normal strain of 200.0 in./in. is produced in the cable by the weight of the cage. at each point, the weight of the cable produces an additional normal strain that is proportional to the length of the cable below the point. assume d = 1800 ft and d = 700 ft. if the total normal strain in the cable at the cable drum (upper end of the cable) is 790 in./in., determine (a) the strain in the cable at a depth of 700 ft. (b) the total elongation of the cable.