In the figure here, a cylinder having a mass of 4.1 kg can rotate about its central axis through point O. Forces are applied as shown: F1 = 6.1 N, F2 = 6.0 N, F3 = 2.9 N, and F4 = 9.5 N. Also, r = 5.7 cm and R = 17 cm. Taking the clockwise direction to be negative, find the angular acceleration of the cylinder. (During the rotation, the forces maintain their same angles relative to the cylinder.)