1. The Milky Way galaxy has about 500,000,000 stars. The Andromeda galaxy has about 1,000,000,000,000 stars. How many stars do the two galaxies have all together?
5 x 10^12 stars
1.0005 x 10^12 stars
5.1 x 10^8 stars
1.0005 x 10^8 stars​