The member OA of the industrial robot telescopes and pivots about the fixed axis at poin...

The member OA of the industrial robot telescopes and pivots about the fixed axis at point O. At the instant shown, - 6 m/s². Determine the magnitudes of the velocity and acceleration of joint A of the robot. Also, sketch the velocity and acceleration of A and determine the angles which these vectors make with the positive x-axis. The base of the robot does not revolve about a vertical axis.