A point charge Q = -400 nC and two unknown point charges, q1 and q2, are placed as shown. Point charge q1 is located 1.3 meters along the +x-axis, point charge q2 is located 0.7 meters down the -y-axis, and point charge Q is located 2.0 meters from the origin at an angle of 30° above the x-axis. At the origin, the three charges together create an electric field that has magnitude zero. What is the charge q1?
150 nC

120 nC

–120 nC

–150 nC

250 nC