One line of a three-phase generator is open-circuited, while the other two are short-circuited to ground. The line currents are \(I_{a}=0, I_{b}=1200 \angle 150^{\circ}\), and \(I_{c}=1200 \angle+30^{\circ} \mathrm{A}\). Find the symmetrical components of these currents. Also find the current into the ground.