A thin, infinitely wide flat sheet lying in the \(xy\)-plane carries a uniform surface current density \(\vec{K} = K\hat{i}\), where \(K\) is constant. An Amperian loop can be used to evaluate the magnetic field produced by this current distribution at points not on the sheet. Which of the following correctly gives the direction of the magnetic field in the region \(z > 0\) and the magnitude \(B\) of the magnetic field on either side of the sheet?