Answer: Yes
Air serves as a propagation medium.
Explanation:
Propagation of sound wave require a medium for transmission. Sound is produced by vibrating objects, The matter or substance through which sound is transmitted is called a medium. It can be solid, liquid or gas. Therefore to propagate sounds (human voice) from one end of a lecture hall to the other we need a propagation medium which is air. Air serves as a propagation medium.
Answer:
Angular speed, 
Explanation:
It is given that,
The top of the leaning bell tower at Pisa, Italy, moved toward the south at an average rate of, v = 1.2 mm/yr

Velocity, 
Height of the tower, h = 55 m
The height of the tower is equivalent to the radius. Let
is the angular speed of the tower’s top about its base. The relation between the angular speed and the angular speed is given by :




So, the average angular speed of the tower’s top about its base is
. Hence, this is the required solution.
<h2><em>The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. As the source of sound waves approaches a listener, the sound waves get closer together, increasing their frequency and the pitch of the sound.</em></h2><h2><em>HOP</em>E IT HELPS </h2><h2>THANK YOU </h2>
The radius of the cylinder is equal to half the diameter:

The volume of the cylinder is given by:

where h is the heigth of the cylinder. Converting into meters,

And the density of the material will be given by the ratio between the mass and the volume:
