Two Small Forward-Facing Speakers Are 2

Multiple Choice

Two small forward-facing speakers are 2.50 m apart.They are both emitting,in phase with each other,a sound of frequency 1100 Hz in a room where the speed of sound is 344 m/s.A woman is standing opposite the midpoint between the speakers and is initially 35.0 m from the midpoint.As she slowly walks parallel to the line connecting the speakers,at what angle θ (relative to the centerline coming outward from the midpoint between the speakers) will she first hear no sound?

A) 0.063°
B) 3.6°
C) 7.2°
D) 1.8°
E) 11°