A Puck on a Frictionless Air Hockey Table Has a Mass

Multiple Choice

A puck on a frictionless air hockey table has a mass of 5.0 kg and is attached to a cord passing through a hole in the surface as in the figure. The puck is revolving at a distance 2.0 m from the hole with an angular velocity of 3.0 rad/s. The angular momentum of the puck (in kg⋅m²/s) is

A) 80
B) 20
C) 30
D) 60
E) 50