When an acrobat hangs motionless from a pair of rings
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she has no measurable weight.
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her weight depends on the angles the ropes make with the ceiling.
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her weight is reduced by the upward force the rings exert on her.
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her weight is increased by the upward force the rings exert on her.
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she exerts a gravitational force on the Earth that is equal to the sum of the forces the rings exert on her.