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A rod of length L is pivoted about its left end and has a force F applied perpendicular to the other end. The force F is now removed and another force F' is applied at the midpoint of the rod: If F' is at an angle of 30 with respect to the rod, what is its magnitude if the resulting torque is the same as when F was applied? a. F b. 2F C. 3F d. 4F