Answer:
part A is the answer
Explanation:
The tympanic cavity is an air chamber; it contains a chain of movable bones which transmit the vibrations of the tympanic membrane across the cavity to the middle ear.
 
        
             
        
        
        
(a) very frequent use of something so that it stops being effective; an over-use.
        
             
        
        
        
Answer:
At the very bottom
Explanation:
When examining a cross section of rock layers, the oldest layer is on the bottom. This is because over time, newer rock layers continued to form on top of the oldest one.
 
        
             
        
        
        
Answer:
right ventricle to left ventricle
Explanation:
 
        
             
        
        
        
Frequency of q allele would be increase then;