How is a light year helpful when describing the the size of a galaxy? Provide an example.

did you fail the test? xd

imagine a line passing through the center of earth that goes through both the north pole and the south pole. this imaginary line is called an axis. earth spins around its axis, just as a top spins around its spindle. this spinning movement is called earth's rotation. at the same time that the earth spins on its axis, it also orbits, or revolves around the sun. this movement is called revolution.

lichens that colonize bare rock secrete acids that break down the rock and start the soil-production process. so they expose rocks