Here’s how the contributions to the theory of universal gravitation match with the scientists:
- Johannes Kepler: Described the motion of planets around the sun as elliptical.
- Robert Hooke: First proposed the idea that a force of attraction applied to all objects in space.
So, place "Described the motion of planets around the sun as elliptical" next to Johannes Kepler, and "first proposed the idea that a force of attraction applied to all objects in space" next to Robert Hooke.