Not necessarily. It is likely possible for a black hole to be ejected from its host galaxy during a galactic collision.
Not all galaxies have black holes. While many galaxies, including our own Milky Way, have supermassive black holes at their centers, there are also galaxies that do not have black holes. The presence of a black hole in a galaxy depends on various factors such as the size and age of the galaxy.
Black holes are a bit hard to detect, so I am pretty sure that not all black holes in this galaxy are known - and I suspect there is not even a decent estimate. But you can expect there to be several.
Not all galaxies, but it is believed that the majority of galaxies have central black holes.
All galaxies have black holes, even the Milky Way.
Not really "a" black hole - many black holes. It is currently believed that all, or most, galaxies have a huge black hole at its center. Any galaxy should also have lots of smaller black holes - so-called "stellar" black holes, because they have approximately the mass of a star (larger stars can become black holes).
Most or all galaxies appear to have supermassive black holes at their centers and probably have stellar mass black holes scattered throughout.
Yes. Our galaxy has a supermassive black hole at its center and likely millions of stellar mass black holes scattered throughout.
Yes. There is a supermassive black hole at the center of the galaxy and a number of stellar mass black holes through the rest of it.
Yes, Black Holes are very common in our galaxy and general.
Yes
Not every galaxy has a black hole at its center. While many galaxies do have supermassive black holes at their centers, there are also galaxies that do not have black holes.
It's not "galaxy stars", but galaxies, that have the black holes at their center.All, or most, galaxies have a giant black hole at their center.