What does the $Adam's \text{ } apple$ represent?

Number of alveoli in human lung is about

The epithelium of the alveoli in the lungs is .......... .

Vocal cords are present in . . . . . . .

Given below are two statements regarding the respiratory system of man.
$Statement-I$: Epiglottis prevents the entry of food into the trachea.
$Statement-II$: The internal lining of the trachea is made up of ciliated epithelium only.
In the light of the above statements, choose the most appropriate answer from the options given below:

The covering of the lungs in humans is known as....