A vertical speaker, which can be viewed as a 30.0-cm gap, is playing a 1.20-kHz tone from the center of the stage, 10.0 m away from the first row of the seats. A listener in the first row tries to avoid the loud sound with sitting off the center of the row. Assuming that the speed of sound in the air is 343 m/s, how far from the center does she have to sit?