1c Sub-question A rigid buoy (Dutch: boei) with center of mass and body-fixed triad B floats in a lake to mark a waterway. b c d e 9 h To keep it close to the waterway, the buoy is anchored to a weight located at the origin O of an inertial coordinate system XYZ associated with a triad N. The weight is connected to the buoy by a flexible chain that runs from point A on the weight to point B on the buoy. A sailor attempts to calculate XMext,p, the sum of external moments acting on the buoy with respect to P, by using the only formula that he knows of: >Mext, P = Ipw+wx (Ipw) where P is some point of reference that the sailor must choose, Ip is the mass moment of inertia tensor of the buoy with respect to point P and the angular velocity of the buoy with respect to the body-fixed frame. Which of the following is allowed as reference point? only P = A only P = B only P=C only P=0 P = B or P =C P = 0 or P =C P = 0 or P = A P=O or P = A or P = C