Which of the following describes one of Galileo Galilei's contributions to the development of the concept of gravity? a. He conducted experiments with balls and inclined planes.
b. He theorized that Earth was at the center of the universe.
c. He theorized that planets move around the Sun in an elliptical pattern.
d. He calculated a value that is currently known as the gravitational constant.

The correct option is;

c. He conducted experiments with balls and inclined planes

Explanation:

The inclined plane experiment conducted by Galileo Galilei was one of his most important experiments.

The experiment consisted of a grooved board with which a small metal ball is rolled down in, so as to analyze the held Aristotelian ideas about motion.

In the experiment, the focus was on acceleration, a concept that the previously held ideas about motion

answer: the correct answer id option(d).

explanation:

snell's law refraction:

the angle of refraction =

the angle of incidence =

refractive index of air = = 1

refractive index of glycerol = 1.47

from the given options, the most closest answer to 63.72° is 65° of option (d).