Question

part a
what newton discovered most about gravity is that it is
view available hint(s)
hint 1.
what is the title of this section?
ever present
another rule of nature, though an important one
the strongest of known forces
universal

Explanation:

Newton's law of universal gravitation states that every particle attracts every other particle in the universe 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. This shows that gravity is a universal force acting between all masses in the universe.

Answer:

universal