Answer:
66.6 or it could be 66.66 one of those
Explanation:
 
        
             
        
        
        
Answer:
0.29D
Explanation:
Given that 
F = G M m / r2
F = GM(6m) / (D-r)2
G Mm/r2 = GM(6m) / (D-r)2
1/r2 = 6 / (D-r)2
r = D / (Ö6 + 1)
r = 0.29 D
See diagram in attached file
 
        
             
        
        
        
Answer:
Opposite charges attract each other.
 
        
                    
             
        
        
        
Gravity adds 9.8 m/s to the downward speed of a falling object every second. (On Earth.)
In 7 seconds, gravity adds (7 x 9.8 m/s) = <em>68.6 m/s</em> to the downward speed of a falling object.
(IF air resistance has no effect on the object.)