**Answer:**

<u>Part A</u>

I = 1.4 mW/m²

<u>Part B</u>

β = 91.46 dB

**Explanation:**

<u>**Part A**</u>

Sound intensity is the power per unit area of sound waves in a direction perpendicular to that area. Sound intensity is also called acoustic intensity.

For a spherical sound wave, the sound intensity is given by;

Where;

**P** is the source of power in watts (W)

**I** is the intensity of the sound in watt per square meter (W/m2)

**r** is the distance r away

Given:

P = 34 W,

A = 1.0 cm²

r = 44 m

The sound intensity at the position of the microphone is calculated to be;

I = 0.0013975 W/m²

≈ I = 0.0014 W/m² = 1.4 × 10⁻³ W/m²

**I = 1.4 mW/m²**

The sound intensity at the position of the microphone is **1.4 mW/m².**

<u>**Part B**</u>

Sound intensity level or acoustic intensity level is the level of the intensity of a sound relative to a reference value. It is a a logarithmic quantity. It is denoted by **β** and expressed in nepers, bels, or decibels.

Sound intensity level is calculated as;

β dB

Where,

**β** is the Sound intensity level in decibels (dB)

**I** is the sound intensity;

**I₀** is the reference sound intensity;

By pluging-in, I₀ is 1.0 × 10⁻¹² W/m²

∴ β

β

**β = 91.46 dB**

The sound intensity level at the position of the microphone is **91.46 dB.**