Which law does this diagram show? a Kepler's second Law: Law of Equal Areas b Newton's first Law: everything in motion will stay in motion unless acted upon by an outside force c Kepler's Third Law: radius cubed is proportional to orbital period squared d Newton's Law of Universal Gravitation

The diagram you mentioned likely illustrates Kepler's Second Law, also known as the Law of Equal Areas. This law states that a line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time, which implies that a planet moves faster when it is closer to the Sun in its elliptical orbit. If the diagram represents the sweeping of equal areas over time, then the answer is (a) Kepler's second Law: Law of Equal Areas.