In unit-vector notation, what is the torque about the origin on a particle located at coordinates (0, -3.54 m, 8.58 m) due to (a) force F→1 with components F1x = 9.69 N and F1y = F1z = 0, and (b) force F→2 with components F2x = 0, F2y = 9.60 N, F2z = 9.72 N?