Final answer:
On a clear, dark night, about 9000 stars are visible with the unaided eye, a small fraction of the billions in the Milky Way Galaxy. The farthest visible stars can be up to 5000 light-years away. An average of 0.22 stars per square degree are visible across the sky.
Step-by-step explanation:
On a clear, dark night, far from the interfering glow of city lights, a person with unaided eyes can see approximately 9000 stars spread across the sky. This number represents the total visible stars from both the northern and southern hemispheres of our planet. It is noteworthy, however, that this is just a tiny fraction of all the stars that exist within our Milky Way Galaxy, as most of them are too faint to be seen without the aid of telescopes.
When asked about the farthest stars visible without a telescope, a good general response is that the brightest stars can be several hundred to a few thousand light-years away, with some exceptional stars being visible up to 5000 light-years from Earth due to their high luminosity.
If we were to distribute the roughly 9000 visible stars across the entire sky, which consists of about 41,200 square degrees, we would have an average of about 0.22 stars visible per square degree. However, the number of stars per square degree can vary widely across different regions of the sky, as the density of stars isn't uniform.