Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occurring in ionic compounds.A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding.
Answer:
I think it is pulling the sled off the ice covered back yard.
Answer:
The amplitude is
Explanation:
From the question we are told that
The frequency of when sound is approaching observer is 
The frequency as the move away from observer is 
The time between the pitch are 
Here you are the observer and your friends are the source of the sound
The period is mathematically evaluated as

as it is the time to complete one oscillation which from on highest pitch to the next highest pitch
Now T can also be mathematically represented as

Where
is the angular velocity
=> 
=> 
Now using Doppler Effect,
The source of the sound is approaching the observer
The


Where A is the amplitude
So when the source is moving away from the observer
Here
is the fundamental frequency
Dividing the both equation we have




=> 

There are several actions that can be used to increase the action force of a canoe that is moving through water. One can increase the rate of striking or strike harder than before with a bigger paddle. Using a lighter canoe can also be helpful for increasing the speed. I hope the answer comes to your help.