A thin, rigid wire bent into a semicircle of radius \(R\) lies in the \(xy\)-plane with its endpoints on the \(x\)-axis at \((R, 0)\) and \((-R, 0)\). The wire carries a steady current \(I\) directed counterclockwise along the arc for \(y \ge 0\). A uniform magnetic field \(\vec{B} = B_0\,\hat{k}\) is directed perpendicular to the \(xy\)-plane. In terms of \(I\), \(R\), and \(B_0\), which of the following expressions correctly gives the net magnetic force \(\vec{F}\) exerted on the semicircular wire?