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Audrae_World
A certain treatment for kidney stones utilizes a water tank in the shape of one of the conic sections. The patient is placed in the tank with the kidney stones at one of the foci and a high-energy source at the other foci. The sum of the distances from the side of the tank to each focus is always constant. What is the shape of the water tank?
|dw:1338682316403:dw| i think this is called a lithotripter??? what is the shape?