Complete Question 
The complete question is shown on the first uploaded image 
Answer:
Explanation:
From he question we are told that 
     The first mass is   
       The second mass is  
From the question we can see that at equilibrium the moment about the point where the  string  holding the bar (where  are hanged ) is attached is zero
 are hanged ) is attached is zero  
    Therefore we can say that 
                
Making x the subject of the formula  
                 
                     
                      
Looking at the diagram we can see that the tension T  on the string holding the bar where  are hanged  is as a result of the masses (
 are hanged  is as a result of the masses ( )
)
      Also at equilibrium the moment about the point where the string holding the bar (where ( )  and
)  and   are hanged ) is attached is  zero
 are hanged ) is attached is  zero 
    So basically 
           
           
  Making  subject
 subject 
           
                 
 
        
             
        
        
        
Find the force that would be required in the absence of friction first, then calculate the force of friction and add them together.  This is done because the friction force is going to have to be compensated for.  We will need that much more force than we otherwise would to achieve the desired acceleration:

The friction force will be given by the normal force times the coefficient of friction.  Here the normal force is just its weight, mg

Now the total force required is:
0.0702N+0.803N=0.873N
 
        
        
        
No waves because Q19 waves would going at the surface at regions
        
             
        
        
        
Answer:
only the weight of the ball will act on the ball
Explanation: There is no contact force on the ball. Also there is no air resistance on the ball so the friction force on the ball due to air is not shown