Complete Question 
The complete question is shown on the first uploaded image 
Answer:
a 
The torque produced by the pile of rocks is  
   
b
 The distance of the single for equilibrium to occur is  
 
Explanation:
From the question we are told that 
      The mass of the left rock is  
      The mass of the rock on the right 
     The distance from  fulcrum to the center of the pile of rocks is  
    
Generally the torque produced by the pile of rock is mathematically represented as
            
Substituting values 
           
                  
            
      
 Generally we can mathematically evaluated the distance of the the single rock that would put the system in equilibrium as follows 
    The torque due to the single rock is 
            
At equilibrium the both torque are equal 
             
Making  the subject of the formula
 the subject of the formula 
              
Substituting values 
              
 
              
 
 
        
             
        
        
        
Answer:
ok so
Explanation:
Im not sure rn but ill get back to you.
 
        
             
        
        
        
Answer: 
atom - 
the smallest particle of a chemical element that can exist.
atomic mass- 
the quantity of matter contained in an atom of an element
atomic weight -
ratio of the average mass of a chemical element's atoms to some standard
protons-
stable subatomic particle that has a positive charge equal in magnitude to a unit of electron charge and a rest mass of 1.67262 × 10−27 kg
electrons-
a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids
neutrons-
a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
energy levels-
one of the stable states of constant energy that may be assumed by a physical system   
[used especially of the quantum states of electrons in atoms and of nuclei. — called also energy state.]
Covalent bonds
the interatomic linkage that results from the sharing of an electron pair between two atoms.
ionic bonds
type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound. 
Valence electrons
a single electron or one of two or more electrons in the outer shell of an atom that is responsible for the chemical properties of the atom.
Lewis Dot Diagram
A way of representing atoms or molecules by showing electrons as dots surrounding the element symbol. One bond is represented as two electrons.
 
        
             
        
        
        
weight less on moon than on earth.
high on lift off - G force
low in orbit.
zero at a point between earth and moon