Question

which statement accurately describes how the understanding of the doppler effect is applied to the study of galaxies?
it was used by hubble to measure the velocities of galaxies
it was used to monitor galaxy motion through changes in sound waves
it indicates a galaxy moving toward earth through red shift
it indicates a galaxy moving away from earth through blue shift

Explanation:

The Doppler - effect was used by Hubble to measure galaxy velocities. Galaxies moving away from Earth show red - shift and those moving towards show blue - shift. Also, in space, we deal with light waves, not sound waves as there is no medium for sound propagation.

Answer:

It was used by Hubble to measure the velocities of galaxies