A rigid, irregular planar object of mass \(M = 2.0\text{ kg}\) is suspended from a horizontal frictionless pivot located at a distance \(d = 0.50\text{ m}\) from its center of mass. The object is displaced by a small angle and released from rest, undergoing small-angle oscillations in a vertical plane. A motion sensor records the object's angular acceleration \(\alpha\) as a function of its angular displacement \(\theta\), resulting in the graph shown. Taking the acceleration due to gravity to be \(g = 10\text{ m/s}^2\), what is the rotational inertia of the object about an axis perpendicular to the plane and passing through its center of mass?