Force Sensor Cart Force Force Time Position Graph 1 Graph 2 25. A cart of known mass moves with known speed along a level, frictionless track, as shown in the figure above. The cart hits a force sensor and rebounds. The force sensor measures the force exerted on the cart as a function of time and as a function of the position of the cart. The results will be graphed on the axes shown. Which of the two graphs can be used to determine the cart's speed after it rebounds? (A) Only graph 1; graph 2 will have no information useful for finding the speed. (B) Only graph 2; graph I will have no information useful for finding the speed. (C) Either graph 1 or graph 2 can be used. (D) Neither graph alone is sufficient; both graph 1 and graph 2 are needed