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* An 80-kg clown sits on a 20-kg bike on a tightrope attached between two trees. The center of mass of the clown is 1.6 m above the rope, and the center of mass of the bike is 0.7 m above the rope. A load of what mass should be fixed onto the bike and hang 1.5m below the rope so that the center of mass of the clown-bike-load system is 0.5 m below the rope? What is the force that the rope exerts on each tree if the angle between the rope and the horizontal is
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