A uniform bar AB of mass m = 100 kg and length L = 4 m is pinned at its end A and is connected to a cable with tensile force P, as shown in the figure. The bar moves in the vertical plane show. At any instant, the angle ? gives the orientation of the bar with respect to the vertical position. Initially, the bar is at rest when ? = 0. a) Draw a free body diagram of bar AB when a tensile force P = 300 N is suddenly applied (initially) at ? = 0. b) Calculate - at this initial instant - the reactions at pin A, the (vector) acceleration aG of the center of mass G of bar AB, and the angular acceleration ?AB of bar AB. (Express all vector results in terms of horizontal unit vector i and vertical unit vector j.) c) Would the result in part b) for the angular acceleration ?AB of bar AB change if bar AB had a non-zero initial angular velocity ?AB? Explain your answer clearly.