A=F/m 
a=(3000000)/(20000)
a=15 m/s^2
        
             
        
        
        
Answer:
The earth's pull on the moon
Explanation:
Earth exerts a gravitational pull on the moon 80 times stronger than the moon's pull on the Earth. 
 
        
             
        
        
        
The answer is cancer that is the reason there is no complete cue in people
        
             
        
        
        
Answer:
 , charges are both positive or both negative
, charges are both positive or both negative
Explanation:
The electrostatic force between the two spheres is given by

where
k is the Coulomb's constant
q1 and q2 are the charges on the two spheres
r is the distance between the centres of the two spheres
In this problem, we have
 is the force
 is the force
 is the distance between the spheres
 is the distance between the spheres
 because the two spheres have identical charge
 because the two spheres have identical charge
Solving the formula for q, we find

And the two charges have the same sign (so, both positive or both negative), since the sign of the force is positive (+0.30 N), so it is a repulsive force.