Answer:
it loaded and it is C. buddy sorry about that :)
 
        
                    
             
        
        
        
This distance is known as the amplitude of the wave, and is the characteristic height of the wave, above or below the equilibrium position. Normally the symbol A is used to represent the amplitude of a wave. The SI unit of amplitude is the metre (m).
        
             
        
        
        
Answer:
Instantaneous speed means speed at any instant 
that means Speed is changing with time 
You know speed is distance/time 
So that means distance is also changing with time 
So we take infinitesimal small distance per infinitesimal small time As we assume speed is constant in infinitesimal small time dt 
So, we take speed = ds/dt 
ds = infinitesimal small distance
dt = infinitesimal small time 
As its ratio is equal to speed at any instant 
Note : We are taking infinitesimal small distance 
But :) we are taking infinitesimal small time also
As you know if denominator is small fraction is large So fraction always give large value 
So it's not O ( this makes confuse to most of students)
So, thanks 
Good question
Keep thinking like this :)
 
        
                    
             
        
        
        
<span>Scientists have documented that the current level of carbon dioxide in the atmosphere is increasing.</span>