Answer:
c) 
Explanation:
Coulomb's law says that the force exerted between two charges is inversely proportional to the square of distance between them, and is given by the expression:

where k is a proportionality constant with the value 
In this case
, so we have:

Solving the equation for q, we have:



Replacing the given values:


Answer:
A) 1.5 v
B) Top plate is at higher voltage than the bottom plate
Explanation:
Battery value set between 0.0 V and 1.5 V
a) The potential difference between the plates
Δ V = V1( potential at top plate) - V2( potential at lower plate )
potential at top plate = 1.5 V
potential at lower plate = 0.0 V
hence potential difference = 1.5 V
b ) The top plate is always connected to the positive terminal of the DC source ( which is at a higher potential )while the bottom plate is connected to the negative terminal of the DC source ( which is at a lower potential )
hence the Top plate is at higher voltage than the bottom plate
As its charge, proton -a positive charged molecule at the center of an atom- is the opposite of the electron -the particle which is orbiting the center of an atom.
When pushing the body it is necessary to break the frictional force generated by the floor. Once this frictional force is overcome, the body will begin to move. Ideally, if a constant velocity is maintained or close to this value, the acceleration that will be exerted will tend to be zero and therefore, by Newton's second law the value of the Force will also tend to minimum values.
Remember that this law tells us that


Therefore the best strategy is A. keep pushing the box forward at a steady speed
The answer to your problem is I believe (B.)