Final answer:
Newton's Fourth Law: Law of Gravitation is not one of Newton's laws of motion.
Step-by-step explanation:
The statement that is not one of Newton's laws of motion is D. Newton's Fourth Law: Law of Gravitation.
Newton's laws of motion consist of:
Newton's First Law: Law of Inertia - A body at rest remains at rest, or, if in motion, remains in motion at a constant velocity unless acted upon by a net external force.
Newton's Second Law: F = ma - The force acting on an object is equal to the mass of the object multiplied by its acceleration.
Newton's Third Law: Action and Reaction - For every action, there is an equal and opposite reaction.
Newton did not propose a Fourth Law of Gravitation. Instead, his work on gravity is described by his law of universal gravitation, which states that every particle of matter in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.