The plank CDE has a weight of 30lb and rests on a small pivot at D. The 110-lb gymnast A is standing on the plank at C when the 140-lb gymnast B jumps from a height of 7.5 ft and strikes the plank at E. Assuming perfectly plastic impact and that gymnast A is standing absolutely straight, determine the height to which gymnast A will rise.

Transcribed Image Text:

-L- D Б h 21