posted by Robby .
Our Milky Way galaxy is very similar to our neighboring galaxy Andromeda. Consider that each galaxy contains approximately 4.0 x 10^11 stars each star having an average mass of 2.0 x 10^30 kg.
a. If the gravitational pull of Andromeda is 2.4 x 10^30 N, how far away is Andromeda?
b. How many light years away is the Andromeda Galaxy? (Note there are 365.25 days per year and light travels at 3.0 x 10^8 m/s).