Angular Collision. A uniform rod of mass M and length d is initially at rest on a horizontal and frictionless table in the x-y plane. the figure attached is a top view, with gravity pointing into the page. The rod is free to rotate about an axis perpendicular to the plane and is passing through the pivot point at a distance d/3 measured from one of its ends as shown. A small point particle of mass m = M/4, which is moving with speed $v_0$, hits the rod and sticks to it at the point of impact at a distance d/3 from the pivot.
$a)$ Find the magnitude of the angular velocity of the rod-and-mass system after the collision.
$b)$ Using again $M = 4m$, find the speed of the centre of mass of the rod right after the collision.
I'm assuming you start to answer this question by using the equation of angular momentum $L = I\omega$ Really confused by this if someone could help me understand the question. Thanks in advance.