46. A sound wave from a sound generator radiates uniformly in all directions in 22.0 ℃air. The sound intensity level is 50 dB at a distance of 4.00 m from the sound generator. The frequency of the sound wave is 500 Hz. At what distance from the sound generator is the sound intensity level 30 dB? (A) 12.6 m (B) 40.0 m (C) 80.0 m (D) 6.67 m (E) 16.0 m