Rod AB is welded to the 12-in.-radius plate which rotates at the constant rate ω 1 =6 rad/s….

Rod AB is welded to the 12-in.-radius plate which rotates at the constant rate ω1 =6 rad/s. Knowing that collar D moves toward end B of the rod at a constant speed θ = 78 in./s, determine, for the position shown, (a) the velocity of D, (b) the acceleration of D.