Instruction:
Which of the following does not fit with the others? Please explain your reasoning.
Galaxy M81
Black Eye Galaxy
Pinwheel Galaxy
Andromeda Galaxy
Sombrero Galaxy

Response:
Galaxy M81 does not fit with the other 4 in the list as M81is a designation rather than a proper name. The other 4 galaxies listed also have a designation, e.g Sombrero Galaxy is designated M104. M81 also has a proper name, Bode's Galaxy. But as listed, Galaxy M81 is distinct from the rest of the list.