A box of mass m = 15 kg is suspended inside an elevator using three identical light vertical ropes. One of the ropes is attached to the ceiling of the elevator, and two are attached to its floor. When the elevator is at rest, the tension in each of the “bottom” ropes is F = 10 N.

Assuming that the ropes obey Hooke’s law, and that thevalue of g = 10 m/s2, find the tension of the “top” rope in two separate cases:

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