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The figure shows an object of mass m=4 kg moving in a vertical circle attached to a massless string of length L=0.6m. When the object is at position A it has unknown speed vo. If the only forces acting on the object are gravity and the tension in the string, and the tension in the string at position A is 240N, what is the tension in the string when the object is at position D? (A) 122 N D (B) 61 N (C) 78 N L C (D) 165 N (E) 93 N