2- The rotation of rod OA about O is defined by the relation θ = (4t² - 8t), where θ and t are expressed in radians and seconds, respectively. Collar B slides along the rod so that its distance from O is r = 10 + 6 sin πt, where r and t are expressed in inches and seconds, respectively. When t = 1 s, determine (a) the velocity of the collar; (b) the total acceleration of the collar, (c) the acceleration of the collar relative to the rod.