In a famous 1654 experiment, Otto von Guericke cast two halves of a 51-cm-diameter sphere. He fit them together so the sphere would not leak, and then he evacuated it. Two teams of eight horses could not pull the hemispheres apart. Later, he tried two teams of 12 horses, but they still could not pull the hemispheres apart. If the sphere was evacuated to 0.1 atmospheres, what force would be required to pull the hemispheres apart?