A Source of Sound Waves Is Placed at the Center

Multiple Choice

A source of sound waves is placed at the center of a very large sound-reflecting wall. The source emits 0.500 W of power. Two meters from the source the intensity in W/m² is

A) 9.95 × 10−³.
B) 1.99 × 10−².
C) 0.313.
D) 0.399.
E) 0.625.