Monochromatic light of frequency \(f\) is directed onto a metal target of work function \(\Phi\), where \(hf > \Phi\). The emitted electrons, each having mass \(m\) and charge magnitude \(e\), immediately enter a region of uniform magnetic field of magnitude \(B\) directed perpendicular to their velocity. Which of the following correctly gives the maximum orbital radius \(R_{\max}\) of the electrons in the magnetic field, and describes how \(R_{\max}\) changes if the intensity of the incident light is doubled at constant frequency \(f\)?