Answer:
In the famous relativity equation, E = mc2, the speed of light (c) serves as a constant of proportionality, linking the formerly disparate concepts of mass (m) and energy (E).
Step-by-step explanation:
By adjusting the path length while observing the interference pattern and carefully measuring the change in path length, the wavelength of the light (λ) can be determined. The speed of light is then calculated using the equation c = λf.