A galaxy is receding away from us with a recession velocity of 100,000 km/s. What is the distance to this galaxy? What is the redshift z of this galaxy?

Answer 1

imagine you have obtained spectra from several galaxies and have measured the Red shift of each galaxy to determine the speed away from us. Here are your results:
Galaxy 1: speed away from us is 10,000 Km/sec.
Galaxy 2: speed away from us in 1,500 Km/sec.
Galaxy 3: speed away from us is 30,000 Km/sec.
extimate the distance to each galaxy from hubble's law. assume that H=23Km/s/Mly