Intensity Of Sound Wave

Define the term intensity of a sound wave. State the unit in which it is measured.

The intensity of a sound wave gets reduced by 20% on passing through a slab. The reduction intensity on passage through two such consecutive slabs

The intensity of a sound wave gets reduced by 20% on passing through a slab. The reduction intensity on passage through two such consecutive slabs

In the previous example, if the density of air r = 1 . 22 kg //m^(3) , then find the intensity of a sound wave of the largest amplitude tolerable to the human ear.