I believe the answer is potential energy if i remember correctly.
Neglecting friction and air resistance, the first hill must be built 4 times higher than it is now.
A scientific law is the simple mathematical expression of the relationship involved. A principle is the same relationship expressed in words. A theory is the explanation of the facts that make up the relationship.
Answer: The speed necessary for the electron to have this energy is 466462 m/s
Explanation:
Kinetic energy is the energy posessed by an object by virtue of its motion.

K.E= kinetic energy = 
m= mass of an electron = 
v= velocity of object = ?
Putting in the values in the equation:


The speed necessary for the electron to have this energy is 466462 m/s