An experiment is conducted to determine the rotational inertia of a cylinder of mass \(M\) and radius \(R\). The cylinder is released from rest and rolls without slipping down a ramp from several different vertical release heights \(h\). For each trial, the translational speed \(v\) of the cylinder is measured when it reaches the flat horizontal track at the bottom. If a best-fit line is fit to a graph of \(v^2\) as a function of \(h\), which of the following expressions correctly represents the shape factor \(\beta\) in the cylinder's rotational inertia \(I = \beta M R^2\) in terms of the slope \(S\) of the graph and physical constants?