Arigid assembly consists of three identical uniform bars with an extra mass attached to one of them, as shown. The assembly can spin freely in the vertical plane about the point connecting the bars. Initially, the assembly is at rest in position A The extra mass is then given a very slight disturbance. Shortly after the assembly is observed to be in position B. Between positions A and B the angular momentum of the system is conserved, because the net force is zero conserved, because the net torque is zero conserved, because the rotational inertia is constant not conserved, because of the torque provided by gravity E) not conserved, because of the torque provided by the force at the prvot pont