As a wave propagates,

Select all that apply

• Option A

  the wave intensity remains constant for a plane wave.

• Option B

  the wave intensity decreases with distance from source and is proportional to inverse of the distance, for a spherical wave.

• Option C

  the wave intensity decreases with distance from source and proportional to inverse square of the distance, for a spherical wave.

• Option D

  total average power of the spherical wave over any spherical surface centered at the source remains same.