A rectangular shelf is attached to a wall by two brackets 12 inches apart at points A and B, as shown in Figure P10.17. A wire with a 10-lbf weight attached to it is hanging from the edge of the shelf at point C. Determine the moment of force about point A and about point B caused by the weight at point C. You can formulate this problem by solving it twice, once for each bracket, or by creating a 2 X 3 matrix for the position vector and another 2 X 3 matrix for the force vector. Each row should correspond to a different bracket. The cross function will return a 2 X 3 result, each row corresponding to the moment about a separate bracket. Figure P10.17 Calculation of moment of force in three dimensions. 12 inches 2 inches 4 inches 10 lbf