Arm ABCD is printed at B and undergoes reciprocating motion such that  = (0.3 sin 4t) rad, where t is measured in seconds and the argument for the sine is in radiaus. Determine t

Arm ABCD is printed at B and undergoes reciprocating motion such that  = (0.3 sin 4t) rad, where t is measured in seconds and the argument for the sine is in radiaus. Determine the largest speed of point A during the motion and the magnitude of the acceleration of point D at this instant.