The three parts of the Earth are Atmosphere, Hydrosphere and Lithosphere.
Atmosphere is the blanket of air that surrounds the earth. It is densest close to the surface and thins out as one moves higher. Atmosphere of Earth contains mainly Nitrogen, followed by Oxygen and small amounts of water vapor, Carbondioxide and other gases.
Lithosphere is the outer most part of the earth's surface. The Earth's crust and the mantle form Lithosphere.
Hydrosphere is the part of the Earth that has water. The Oceans, seas, rivers, lakes and other water bodies constitute the Hydrosphere.
Stratosphere, Mesosphere and Ionosphere are different layers of atmosphere.
Hence, for the study of the Earth, one needs to consider earth to be made of three parts- atmosphere, Lithosphere and Hydrosphere.
 
        
                    
             
        
        
        
The least number of component of a vector quantity is two. These are the x-component and the y-component. 
The resultant vector, or vector as we refer to it in this item, can be calculated through the equation,
              RV = sqrt ((Vx)² + (Vy)²)
From the equation, it can be noted that if we let Vx equal to zero,
              RV = Vy
Similarly, if we let Vy be equal to zero then,
             RV = Vx
Thus, it is still possible for the vector to become nonzero even if one of its components is zero. 
        
             
        
        
        
Let  be the height of the building and thus the initial height of the ball. The ball's altitude at time
 be the height of the building and thus the initial height of the ball. The ball's altitude at time  is given by
 is given by

where  is the acceleration due to gravity.
 is the acceleration due to gravity.
The ball reaches the ground when  after
 after  . Solve for
. Solve for  :
:


so the building is about 16 m tall (keeping track of significant digits).
 
        
             
        
        
        
I think it’s B hope it helps:)
        
                    
             
        
        
        
Answer:
 just divide 22 N by 20 kg to get the acceleration in m/s2 
Explanation:
I hope this is right-