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This is Giancoli Answers with Mr. Dychko. The torque exerted by this diver about support post A is gonna be the diver's weight mg multiplied by their distance to the support A which I have labeled l subscript D for the lever arm of the diver. And we can solve for mass by dividing both sides by gl D and so that mass is gonna be torque divided by gl D and that's 1800 newton meters divided by 9.8 newtons per kilogram times 3.0 meters plus 1.0 meter so that's a total of 4.0 meters away from between the support post and the diver and that gives about 46 kilograms.