One significant result of the Michelson experiment of 1880 was that it:

measured man's reaction time

accurately measured the speed of light in the air

calculated the speed of light over a short distance.

calculated the speed of light over a short distance

Explanation:

Albert Michelson was an American physicist who conducted an experiment regarding the speed of light in the air 1880s. He believed in the existence of "aether," a field of space that is deemed necessary for transporting electromagnetic forces. In order to do this, he setup a device in order to accurately measure the speed of light in in aether. His device is now known as "Michelson interferometer." The result was actually negative.

In order to make his experiment even more accurate, he collaborated with Edward Morley, a famous American scientist. Although the result failed, together, they were able to improve and come with the a standard length of light. This calculated the speed of light over a short distance, which was the significant result of Michelson's experiment.

Thus, this explains the answer.

Answer: "accurately measured the speed of light in the air."

Explanation:

*Galileo "measured man's reaction time."

*Fizeau "calculated the speed of light over a short distance."

( + I answered this correctly on the quiz.)