PL HURR Which of these systems can be explained by Newton’s laws of motion and gravitation?
SELECT ALL THAT APPLY
A. the motion of a race car on a racetrack
B. the motion of Earth around the Sun
C. the motion of a ball falling on Earth
D. the motion of electrons in an atom

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.